aaPanel_Kern aaP_noyelshen Hi, Check the mail score and troubleshoot according to its error message https://www.mail-tester.com/ Check blacklists https://mxtoolbox.com/ Sending to gmail needs to configure SSL, do DKIM, SPF, it is best to let the network provider make the PTR RDNS record of ip
aaP_noyelshen There was a problem with DKIM and SPF, also missing PTR Records. error fixed thank you for your advices 🙂