diff --git a/src/mms/iso_mms/client/mms_client_connection.c b/src/mms/iso_mms/client/mms_client_connection.c
index cc63582bb..b635d5167 100644
--- a/src/mms/iso_mms/client/mms_client_connection.c
+++ b/src/mms/iso_mms/client/mms_client_connection.c
@@ -3870,7 +3870,7 @@ struct fileReadParameters
 };
 
 static void
-fileReadHandler(uint32_t invokeId, void* parameter, MmsError mmsError, int frsmId, uint8_t* buffer, uint32_t byteReceived,
+fileReadHandler(uint32_t invokeId, void* parameter, MmsError mmsError, int32_t frsmId, uint8_t* buffer, uint32_t byteReceived,
         bool moreFollows)
 {
     (void)invokeId;
diff --git a/src/mms/iso_mms/client/mms_client_files.c b/src/mms/iso_mms/client/mms_client_files.c
index 4fca418e2..3a6895ebd 100644
--- a/src/mms/iso_mms/client/mms_client_files.c
+++ b/src/mms/iso_mms/client/mms_client_files.c
@@ -731,7 +731,7 @@ mmsMsg_parseFileOpenResponse(uint8_t* buffer, int bufPos, int maxBufPos, int32_t
 }
 
 bool
-mmsMsg_parseFileReadResponse(uint8_t* buffer, int bufPos, int maxBufPos, uint32_t invokeId, int frsmId, bool* moreFollows, MmsConnection_FileReadHandler handler, void* handlerParameter)
+mmsMsg_parseFileReadResponse(uint8_t* buffer, int bufPos, int maxBufPos, uint32_t invokeId, int32_t frsmId, bool* moreFollows, MmsConnection_FileReadHandler handler, void* handlerParameter)
 {
     int length;
     uint8_t* data = NULL;