Error in sending email

Your software
My Mautic version is: 3.1.0
My PHP version is: 7.3
My Database type and version is:

Your problem
My problem is: in setting → configuration → email setting → sen test email → i’m getting error: Expected response code 354 but got code “554”, with message "554 5.5.1 Error: no valid recipients " and also get a error in fetch IP lookup Data Store .

These errors are showing in the log: email settings

Steps I have tried to fix the problem: set up the cronJobs and dkim spf records also