Approval for I-129F in May 2022 - HAVE NOT RECEIVED NVC Welcome letter 8 months later

[TimInFlorida]

Hello,
we were approved for a petition I-129F after 11 months in May 2022
Received I-797 Notice of Action from USCIS with WAC-umber and and A-number.

NVC has never responded with Welcome Letter or Case Number.
The case is stuck here.
We have been waiting for 8 months now.

Is this a normal delay, nowadays?

What could be the reason?
What can one do?

I would appreciate any help.