Ok finally I found out what was wrong. I'm using nostdress connected to my LND node to generate the invoices and publish the zap receipts (9735). And I was using my own private key to sign the receipts. I didn't pay attention to nostdress config doc which said to not use your own. I quickly checked nip-57 and didn't see anywhere mention to not use your own privKey to sign the receipt. Since Amethyst's NotificationFeedFilter has a filter condition to exclude events which author is the loggedInUser it explains the behaviour I was getting. After changing to a new generated privKey to sign the receipts everythingd seems to be working. Do you know the reason it shouldn't use its own privKey to sign the receipt?