The forerunner 45s update to 3.8 does no take effect > remains on 3.6

The forerunner 45s update to 3.8 does no take effect on my watch.

Every time I connect the watch to Garmin Express it suggests to install 3.8, but after the update on the watch it is stil on 3.6

Does anyone have a clue how I get out of this loop? Thank you in Advance!

Daniel