diff --git a/pkg/internal/server/api/stickers_api.go b/pkg/internal/server/api/stickers_api.go
index b6f81cf..231a367 100644
--- a/pkg/internal/server/api/stickers_api.go
+++ b/pkg/internal/server/api/stickers_api.go
@@ -77,9 +77,9 @@ func createSticker(c *fiber.Ctx) error {
 
 	if strings.SplitN(attachment.MimeType, "/", 2)[0] != "image" {
 		return fiber.NewError(fiber.StatusBadRequest, "sticker attachment must be an image")
-	} else if width, ok := attachment.Metadata["width"].(int64); !ok {
+	} else if width, ok := attachment.Metadata["width"]; !ok {
 		return fiber.NewError(fiber.StatusBadRequest, "sticker attachment must has width metadata")
-	} else if height, ok := attachment.Metadata["height"].(int64); !ok {
+	} else if height, ok := attachment.Metadata["height"]; !ok {
 		return fiber.NewError(fiber.StatusBadRequest, "sticker attachment must has height metadata")
 	} else if width != 28 || height != 28 {
 		return fiber.NewError(fiber.StatusBadRequest, "sticker attachment must be a 28x28 image")