Issue #6274 added the break for once the valid time duration is found

Implemented the fix as suggested in #6274 (comment).

redbot/cogs/mutes/converters.py

@@ -52,6 +52,7 @@ async def convert(
             for k, v in time.groupdict().items():
                 if v:
                     time_data[k] = int(v)
+            break # Break after the first valid match
         if time_data:
             try:
                 result["duration"] = timedelta(**time_data)