WebAffair

To create your profile, it will ask for a credit card "to verify age." Credit cards do not verify age. It is an excuse to access your money. It also rejects a pre-paid debit card (nothing to steal.).
Unlike other such sites, after rejecting my debit card, it still sent a confirmatory email that gave me a free membership -- but a free membership does not allow you to even read, let alone answer, messages.
You most likely got sent to this site from an email from someone you met on a dating site. It comes from a bot -- says they haven't received your emails or haven't heard from you in a long time, even though this is your first direct contact. (and despite being told on the dating site that I would not go to another site.)