Why didn't my Level 1 Barbarian become Level 2 when donated?

Solution 1:

This is a very occasion and has happened to me, but once you close and re open the app, the troops will be shown as upgraded. Even if it shows as level 1 to you, he actually received Level 2 Barbarian.

Solution 2:

This is a visual glitch where the level of the troops does not appear.

The troop has been levelled up, but you can not see it. This even happens to troops which are higher than level one causing to appear as if they have been downgraded

Reopening the app should fix this