SMTP TLS v1 issue

We have installed new server and starting customer migration. And the following problem arise - some PHP scripts, that are using SMTP and TLS to connect to server - are not able to do it anymore. In the exim_mainlog I see these related messages: 2023-10-26 14:59:08 SMTP connection from [46.255.21.130]:20596 (TCP/IP connection count = 2) 2023-10-26 14:59:08 no host name found for IP address 46.255.21.130 2023-10-26 14:59:08 TLS error on connection from (