DNS resolve issue

Hi community, I have an Asterisk server running perfecly on the clouds, DNS setting configured properly but i always have theses log messages on my console and is only with the IP address of a remote client ( I dont undestand why Asterisk try to resolve this IP address there is not any domain name on my sip.conf associated with this address

There is a syntax error in the incoming address. There can only be one :

Thanks for the clarification David. That was exactly the issue.