eM Client has stopped receiving and sending mail

Hi there,
I have downloaded eM Client version 6.0.22344.0. a few months ago. Last week it stopped sending and receiving e-mails. No error message appears but nothing happens. E-mails are still coming and going grand from gmail when I use it on chrome or my phone. When I went into Tools>Accounts>Diagnostics and IMAP and SMTP show up as unknown and when I press diagnose it won’t fix it and sometimes I get the attached error message, and it wont recognise my username or password. Any help would be really appreciated as this was a really nice e-mail application until this happened. 

Hello Sinead,
I suggest updating to the latest release 6.0.23421 > http://www.emclient.com/dist/v6.0.234… and then please let us know if the problem occurs.

Best regards,