On Tuesday, April 19, 2022 2:28:01 PM CEST 55578 via tor-relays wrote:
Probably because obfs4 is not installed or not running properly.
Get the obfs4proxy package from backports. Outdated obfs bridges are rejected AFAIK.
https://lists.torproject.org/pipermail/tor-relays/2022-March/020447.html