Ok and as it is fixed because I do not give the solution to the problem, I have been looking for a solution for a long time I need to be able to send emails with the domain that agrees with the server, if not, so I want a VPS.
Besides, where are you seeing that?
He tried many possible solutions searching the Internet and I have not found any that works, the domain of farewellsexclusivas.com works perfectly are the other 2 domains that fail in the DKIM signature, why fails is what I would like to know? and if Amavisd does not use it, it is interfering with the signature in some way.