Public IP access error [resolved]

Hello, everyone.
I had this issue: could not connect the vacuum to my lan. So I reseted the router. Once done that I had to reopen the ports in the router. Finally was able to acces my box via ssh (it had a new ip in lan). Almost everything works BUT I can’t access my box using WHat did I do wrong? WHat did I not do? How can I make it accessible again from WAN? Apparently all ports are open, and the only error (apart of the reverse DNS which for the moment is unsolvable - Orange justo won’t do it, hehe) that appears is (":heavy_multiplication_x: MTA-STS policy is missing: STSFetchResult.FETCH_ERROR).
I can access it like this: (or mail, of course). I can send mail and I receive mail (just checked).
Could anyone help me understand why can’t I access it using my public.ip? (nor using my domain - I have it with
Thanks in advance…

I answer myself: please, do not shoot: I forgot to map the 443 port. Now it’s all working just perfect.
Please, consider this topic solved and closed.