This sounds like it may be an issue with osTicket itself, not an osTicket Awesome issue.
I did want to at least take a look and try to understand what is going wrong before saying so.
But unfortunately I can’t access your installation:
NET::ERR_CERT_COMMON_NAME_INVALID
Further, Chrome says:
You cannot visit helpdesk.stbarnabashospice.co.uk right now because the website uses HSTS.
Let me know when you have your SSL issue sorted and I’ll take a look.