diff --git a/tgbotapi.api/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/api/stickers/AddStickerToSet.kt b/tgbotapi.api/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/api/stickers/AddStickerToSet.kt
index cc167680ba..275d372f8a 100644
--- a/tgbotapi.api/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/api/stickers/AddStickerToSet.kt
+++ b/tgbotapi.api/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/api/stickers/AddStickerToSet.kt
@@ -33,7 +33,10 @@ suspend fun TelegramBot.addStickerToSet(
             emojis,
             keywords
         )
-        StickerType.Mask -> error("Unable to create Mask sticker to the set without maskPosition parameter")
+        StickerType.Mask -> InputSticker.Mask(
+            sticker,
+            emojis
+        )
         StickerType.Regular -> InputSticker.WithKeywords.Regular(
             sticker,
             emojis,
@@ -48,7 +51,7 @@ suspend fun TelegramBot.addStickerToSet(
     stickerSet: StickerSet,
     sticker: InputFile,
     emojis: List<String>,
-    maskPosition: MaskPosition
+    maskPosition: MaskPosition? = null
 ) = addStickerToSet(
     userId,
     stickerSet.name,
@@ -87,7 +90,7 @@ suspend fun TelegramBot.addStickerToSet(
     stickerSet: StickerSet,
     sticker: InputFile,
     emojis: List<String>,
-    maskPosition: MaskPosition
+    maskPosition: MaskPosition? = null
 ) = addStickerToSet(
     user.id, stickerSet, sticker, emojis, maskPosition
 )
diff --git a/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/requests/stickers/InputSticker.kt b/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/requests/stickers/InputSticker.kt
index aaac6fc0cc..9633b555a7 100644
--- a/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/requests/stickers/InputSticker.kt
+++ b/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/requests/stickers/InputSticker.kt
@@ -23,7 +23,7 @@ sealed interface InputSticker {
         @SerialName(emojiListField)
         override val emojisList: List<String>,
         @SerialName(maskPositionField)
-        val maskPosition: MaskPosition
+        val maskPosition: MaskPosition? = null
     ) : InputSticker
 
     @Serializable
diff --git a/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/types/files/Sticker.kt b/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/types/files/Sticker.kt
index c95fc364d4..bd4c1403ee 100644
--- a/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/types/files/Sticker.kt
+++ b/tgbotapi.core/src/commonMain/kotlin/dev/inmo/tgbotapi/types/files/Sticker.kt
@@ -93,7 +93,7 @@ object StickerSerializer : KSerializer<Sticker> {
                     surrogate.file_unique_id,
                     surrogate.width,
                     surrogate.height,
-                    surrogate.mask_position ?: error("For mask stickers field mask_position should be presented"),
+                    surrogate.mask_position,
                     surrogate.thumb,
                     surrogate.emoji,
                     surrogate.set_name,
@@ -104,7 +104,7 @@ object StickerSerializer : KSerializer<Sticker> {
                     surrogate.file_unique_id,
                     surrogate.width,
                     surrogate.height,
-                    surrogate.mask_position ?: error("For mask stickers field mask_position should be presented"),
+                    surrogate.mask_position,
                     surrogate.thumb,
                     surrogate.emoji,
                     surrogate.set_name,
@@ -115,7 +115,7 @@ object StickerSerializer : KSerializer<Sticker> {
                     surrogate.file_unique_id,
                     surrogate.width,
                     surrogate.height,
-                    surrogate.mask_position ?: error("For mask stickers field mask_position should be presented"),
+                    surrogate.mask_position,
                     surrogate.thumb,
                     surrogate.emoji,
                     surrogate.set_name,
@@ -128,7 +128,7 @@ object StickerSerializer : KSerializer<Sticker> {
                     surrogate.file_unique_id,
                     surrogate.width,
                     surrogate.height,
-                    surrogate.custom_emoji_id ?: error("For mask stickers field mask_position should be presented"),
+                    surrogate.custom_emoji_id ?: error("For custom emoji stickers field custom_emoji_id should be presented"),
                     surrogate.thumb,
                     surrogate.emoji,
                     surrogate.set_name,
@@ -139,7 +139,7 @@ object StickerSerializer : KSerializer<Sticker> {
                     surrogate.file_unique_id,
                     surrogate.width,
                     surrogate.height,
-                    surrogate.custom_emoji_id ?: error("For mask stickers field mask_position should be presented"),
+                    surrogate.custom_emoji_id ?: error("For custom emoji stickers field custom_emoji_id should be presented"),
                     surrogate.thumb,
                     surrogate.emoji,
                     surrogate.set_name,
@@ -150,7 +150,7 @@ object StickerSerializer : KSerializer<Sticker> {
                     surrogate.file_unique_id,
                     surrogate.width,
                     surrogate.height,
-                    surrogate.custom_emoji_id ?: error("For mask stickers field mask_position should be presented"),
+                    surrogate.custom_emoji_id ?: error("For custom emoji stickers field custom_emoji_id should be presented"),
                     surrogate.thumb,
                     surrogate.emoji,
                     surrogate.set_name,
@@ -276,7 +276,7 @@ data class RegularVideoSticker(
 
 @Serializable
 sealed interface MaskSticker : Sticker {
-    val maskPosition: MaskPosition
+    val maskPosition: MaskPosition?
 }
 @Serializable
 data class MaskSimpleSticker(
@@ -289,7 +289,7 @@ data class MaskSimpleSticker(
     @SerialName(heightField)
     override val height: Int,
     @SerialName(maskPositionField)
-    override val maskPosition: MaskPosition,
+    override val maskPosition: MaskPosition? = null,
     @SerialName(thumbnailField)
     override val thumbnail: PhotoSize? = null,
     @SerialName(emojiField)
@@ -314,7 +314,7 @@ data class MaskAnimatedSticker(
     @SerialName(heightField)
     override val height: Int,
     @SerialName(maskPositionField)
-    override val maskPosition: MaskPosition,
+    override val maskPosition: MaskPosition? = null,
     @SerialName(thumbnailField)
     override val thumbnail: PhotoSize? = null,
     @SerialName(emojiField)
@@ -335,7 +335,7 @@ data class MaskVideoSticker(
     @SerialName(heightField)
     override val height: Int,
     @SerialName(maskPositionField)
-    override val maskPosition: MaskPosition,
+    override val maskPosition: MaskPosition? = null,
     @SerialName(thumbnailField)
     override val thumbnail: PhotoSize? = null,
     @SerialName(emojiField)