diff --git a/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/Header.kt b/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/Header.kt
index d3e1782..a71df18 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/Header.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/Header.kt
@@ -7,8 +7,6 @@ import kotlinx.serialization.json.*
 
 @Serializable
 data class Header(
-    @SerialName("user_id")
-    val userId: Int,
     @SerialName("account_type")
     val accountType: String,
     @SerialName("short_limit")
@@ -35,7 +33,9 @@ data class Header(
     @SerialName("query_image")
     val queryImage: String, // something like "uuid.jpg"
     @SerialName("results_returned")
-    val resultsCount: Int
+    val resultsCount: Int,
+    @SerialName("user_id")
+    val userId: Int? = null
 )
 
 object IndexesSerializer : KSerializer<List<HeaderIndex?>> {
diff --git a/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/HeaderIndex.kt b/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/HeaderIndex.kt
index e1efa2b..dfc37ba 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/HeaderIndex.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/HeaderIndex.kt
@@ -1,14 +1,11 @@
 package com.github.insanusmokrassar.SauceNaoAPI.models
 
-import kotlinx.serialization.Optional
 import kotlinx.serialization.Serializable
 
 @Serializable
 data class HeaderIndex(
     val status: Int,
     val id: Int,
-    @Optional
     val results: Int = 0,
-    @Optional
     val parent_id: Int? = null
 )
diff --git a/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/ResultData.kt b/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/ResultData.kt
index 6ba44ca..9b8a7ed 100644
--- a/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/ResultData.kt
+++ b/src/main/kotlin/com/github/insanusmokrassar/SauceNaoAPI/models/ResultData.kt
@@ -2,48 +2,35 @@ package com.github.insanusmokrassar.SauceNaoAPI.models
 
 import com.github.insanusmokrassar.SauceNaoAPI.utils.CommonMultivariantStringSerializer
 import kotlinx.serialization.*
-import kotlinx.serialization.internal.ArrayListSerializer
-import kotlinx.serialization.internal.StringSerializer
 
 @Serializable
 data class ResultData(
     @Serializable(CommonMultivariantStringSerializer::class)
     @SerialName("danbooru_id")
-    @Optional
     val danbooruId: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
     @SerialName("gelbooru_id")
-    @Optional
     val gelbooruId: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
     @SerialName("drawr_id")
-    @Optional
     val drawrId: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
     @SerialName("pixiv_id")
-    @Optional
     val pixivId: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
-    @Optional
     val title: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
-    @Optional
     val creator: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
-    @Optional
     val material: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
     @SerialName("member_name")
-    @Optional
     val memberName: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
     @SerialName("member_id")
-    @Optional
     val memberId: String? = null,
     @Serializable(CommonMultivariantStringSerializer::class)
-    @Optional
     val characters: String? = null,
     @SerialName("ext_urls")
-    @Optional
     val extUrls: List<String> = emptyList()
 )