TheBat! mail client DOES NOT WORK since 05/18/2015

TheBat! mail client DOES NOT WORK since 05/18/2015

I can not receive mail through TheBat! mail client since 05/18/2015.
If I understand correctly, the email client should automatically update the certificate, but that did not happen.
Or the problem lies elsewhere?
How to solve the problem?
Thanks!