To fix the problem with the IKEv2 site-to-site tunnel between an ASA and a remote peer based on the debug output, you should ensure that the crypto IPsec policy matches on both VPN devices. The debug output indicates that the crypto policies on the two VPN devices are mismatched, which is preventing the tunnel from building successfully. Installing the correct certificate to validate the peer, correcting the crypto access list on both VPN devices, and specifying the peer IP address in the tunnel group name will not fix the problem.