Upgrade to TrueNAS - now Mac only sees shares through smb

[verada12]

Been using FreeNAS 11.3 as home server for about 2 years - really basis setup. Decided to upgrade to TrueNAS and ran into problem..
Windows 10 sees shares normally but old Mac High Sierra can now only access shares through smb.
If I toggle AFP off/on on TrueNAS server the Mac can access the shared files normally again.
However if I log out/in Mac have to toggle AFP off/on again.
Any thoughts?
BTW I'm a Windows user so not too experienced with TrueNAS - just enough to get by...
Cheers