diff --git a/sat/plugins/plugin_xep_0234.py b/sat/plugins/plugin_xep_0234.py
index bc4c24c1..7ece2f18 100644
--- a/sat/plugins/plugin_xep_0234.py
+++ b/sat/plugins/plugin_xep_0234.py
@@ -179,6 +179,12 @@ class XEP_0234(object):
         if kwargs:
             file_data = file_data.copy()
             file_data.update(kwargs)
+        try:
+            file_data["mime_type"] = (
+                f'{file_data.pop("media_type")}/{file_data.pop("media_subtype")}'
+            )
+        except KeyError:
+            pass
         return self.buildFileElement(client, **file_data)
 
     async def parseFileElement(