My guess is
Try to curl the LNURL-pay endpoint derived from the recipient’s Lightning address:
curl -iL -H 'Accept: application/json' \
https://primal.net/.well-known/lnurlp/anantonio
A Lightning address in the form [email protected] resolves to:
https://primal.net/.well-known/lnurlp/anantonio
JSON containing fields such as tag: "payRequest", callback, minSendable, and maxSendable. If it returns HTML, an empty body, or a server error, that explains Primal’s Json error: expected value at line 1 column 1. Lightning Address uses this standardized /.well-known/lnurlp/<username> format.
