nginx:1.17 works fine, but all versions above don't want it and give an error. It seems that the server does not work correctly, and does not work consistently
on domain/.well-known/acme-challenge/bzZal6pfklWX4kaQTb2x8s6PEI1MqFeN06ZtXA9_Dvs: Connection refused.
First, is domain.com your actual domain name? Because that is a valid domain. It is difficult to help without knowing your real domain and you should have been given a form when posting asking for this. In any case, please do not use names that do not belong to you.
As for your problem, that sounds like a config problem with nginx or your comms setup. The sample nginx config you show has ssl certs. Do you have valid certs at that folder location?