According to Pinnacle support ( Joanne Scott ) need to import the certificate from the server.

https://ask.sage.co.uk/scripts/ask.cfg/php.exe/enduser/std_adp.php?p_faqid=32050&p_pv=0

also had to apply this fix :

I found this on ask sage can you give it a try please

https://ask.sage.co.uk/scripts/ask.cfg/php.exe/enduser/std_adp.php?p_faqid=37417&p_pv=1.584

Hi I think this is working now, there was 2 certificate on server, I installed the other one and that message is gone now