Well, it’s hard to tell not knowing the domain, but an easy test is to create a test file:
echo "Hello" > /usr/local/A1/.well-known/acme-challenge/test.txt
and try to access it directly at http://A1.xxxx.com/.well-known/acme-challenge/test.txt .
If that doesn’t succeed, you’ll need to identify why (mismatched webroots? permissions error in Apache error_log? domain doesn’t point to this server? etc).