I didn't realize you hadn't used the standard .ttf format, .fnt isn't compatible with TMPro and all the software needed to convert it, is only working on MAC. Wasted about 5 hours trying to get a converter working. Could of drawn my own font in that time. Very disappointing.
I don't recommend these files to anyone using Unity as you won't be able to use the up to date rendering architecture. The old text system will be fully depreciated. The description shouldn't claim unity support.