Error messages when setting up customer [missing "en.activerecord.models.fuji_contacts/customer" translation]

I am a current accounting student and am using Sage for a current module. There appears to be an error on my account and all the headings have been replaced with an error message (like the one one in the subject line). Any advice would be greatly appreciated, I've looked through the settings but can't see anything that might affect it.

Thanks!