After update: Default deny rule blocking packets

[MTenzer]

Hi there,
I had version 21.1.9_1 running. After updating to 21.7 or even up to 21.7.3_3, I have the above issue.
Several rules are suddenly ignored and the default rule blocks traffic.

Until yesterday, a snapshot restore to 21.1.9_1 always helped.

Yesterday then, a colleague changed the config and now the error is permanent.
No matter what I try, these packets are blocked.
Any help is appreciated.

Best regards,
Marco

Added:
The specific rules do not have clone or edit buttons. Seems strange.