How to trigger playlist update on Apple Watch

[gue22]

Have come to love the VLC app on Apple Watch, but the playlist gets out of sync with the iPhone even with WLAN on.
How can I trigger a playlist update on the Apple Watch?
TIA
G.

[gue22]

Additional info: I force-quit VLC on the Watch by long-pressing the side-button and then the crown, but that didn´t help either.
Even uninstalling the VLC Watch part and reinstalling it via the Watch app on the iPhone didn´t help.
Checked all settings, but didn´t find anything.
TIA
G.

[gue22]

When I finally thought I had nailed the culprit (the no-shows have accents (a back-tick à and a grave é) in the file names), the files showed on the Watch.

In the meantime I have updated to watchOS to 4.2.3, which is mostly about some weird Indian characters causing crashes. I have no way to tell if the update or the reboot or sth else caused the files to appear -- or I overlooked them alphabetically.

[gue22]

Here we go again. Still looking for a pattern what triggers a VLC playlist update on the Apple Watch. Eventually it got updated, but neither a Watch app or a Watchrestart nor an app close on the iPhone (all with WLAN on) did the trick.
Thanks for any insight!
G.