diff --git a/src/main/kotlin/com/ecwid/apiclient/v3/dto/customer/request/CustomersSearchRequest.kt b/src/main/kotlin/com/ecwid/apiclient/v3/dto/customer/request/CustomersSearchRequest.kt
index 1d5d803ba..e9e7c61cd 100644
--- a/src/main/kotlin/com/ecwid/apiclient/v3/dto/customer/request/CustomersSearchRequest.kt
+++ b/src/main/kotlin/com/ecwid/apiclient/v3/dto/customer/request/CustomersSearchRequest.kt
@@ -10,7 +10,7 @@ data class CustomersSearchRequest(
 	val keyword: String? = null,
 	val name: String? = null,
 	val email: String? = null,
-	val customerGroupId: Int? = null,
+	val customerGroupId: String? = null,
 	val minOrderCount: Int? = null,
 	val maxOrderCount: Int? = null,
 	val minSalesValue: Int? = null,
@@ -62,7 +62,7 @@ data class CustomersSearchRequest(
 			request.keyword?.let { put("keyword", it) }
 			request.name?.let { put("name", it) }
 			request.email?.let { put("email", it) }
-			request.customerGroupId?.let { put("customerGroup", it.toString()) }
+			request.customerGroupId?.let { put("customerGroup", it) }
 			request.minOrderCount?.let { put("minOrderCount", it.toString()) }
 			request.maxOrderCount?.let { put("maxOrderCount", it.toString()) }
 			request.minSalesValue?.let { put("minSalesValue", it.toString()) }
diff --git a/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt b/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt
index dc669863d..347f769f4 100644
--- a/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt
+++ b/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt
@@ -173,8 +173,8 @@ class CustomersTest : BaseEntityTest() {
 
 		assertCustomersSearch(
 			positiveCustomerId = customerCreateResult.id,
-			positiveSearchRequest = CustomersSearchRequest(customerGroupId = customerCreateRequest.newCustomer.customerGroupId),
-			negativeSearchRequest = CustomersSearchRequest(customerGroupId = 0)
+			positiveSearchRequest = CustomersSearchRequest(customerGroupId = customerCreateRequest.newCustomer.customerGroupId.toString()),
+			negativeSearchRequest = CustomersSearchRequest(customerGroupId = "0")
 		)
 
 		assertCustomersSearch(