Domain verification failure

Hi All, I'm trying to verify a domain but I only see the message "Domain verification failed." no other details. From my nginx server log I can see that the file apple-developer-merchantid-domain-association.txt is perfectly reachable

17.179.144.195 - - [19/May/2022:14:01:28 +0200] e948efdd5079b3dcfe8a5f2deddc9279 "GET /.well-known/apple-developer-merchantid-domain-association.txt HTTP/1.0" 200 5673 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/601.7.7 (KHTML%2C like Gecko) Version/9.1.2 Safari/601.7.7" "17.179.144.195"

Could someone suggest me from where to start debugging such situation?

Thanks in advance Accursio

Domain verification failure
 
 
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