Apple Watch music sync from personal playlist stuck on watchOS 26

Apple Watch music sync from own playlist without Apple Music subscription with watchOS 26 stuck after one or two songs while trying.

I tried it all, reset, unpairing, WiFi both on same connection is just fine, both devises charging, Storage is fine, Bluetooth on both sides, but since weeks now no progress on beta and now with official updates.

After one or a couple of songs it is stuck trying to sync but nothing happens.

I need help.

Thanks in advance.

[Edited by Moderator]