I ignore them?. Postfix: warning: hostname does not resolve to address Name or service not known

Hello

I receive these warnings:

Code:Feb 23 20:09:35 mail postfix/smtps/smtpd[5215]:warning: hostname zg0213a-376.stretchoid.com does not resolve to address 12.243.13.139: Name or service not known
Feb 23 20:09:35 mail postfix/smtps/smtpd[5215]: warning: TLS library problem: error:1408F10B:SSL routines:ssl3_get_record:wrong version number:../ssl/record/ssl3_record.c:332:
Feb 23 20:34:33 mail postfix/submission/smtpd[5914]: warning: hostname zg0213a-190.stretchoid.com does not resolve to address 12.21.226.132: Name or service not known
Feb 23 21:10:00 mail postfix/smtps/smtpd[7602]: warning: hostname zg0213a-315.stretchoid.com does not resolve to address 12.243.129.51: Name or service not known
Feb 23 21:10:00 mail postfix/smtps/smtpd[7602]: warning: TLS library problem: error:1408F10B:SSL routines:ssl3_get_record:wrong version number:../ssl/record/ssl3_record.c:332:
Feb 23 21:35:45 mail postfix/submission/smtpd[8375]: warning: hostname zg0213a-128.stretchoid.com does not resolve to address 12.21.221.42: Name or service not known
Feb 23 22:13:04 mail postfix/smtps/smtpd[10064]: warning: hostname zg0213a-140.stretchoid.com does not resolve to address 12.21.21.239: Name or service not known
I am ignoring them, but there are many every day and the vast majority correspond to the IP of the VPS provider where I am testing.

I ignore them?

Thanks