Dee Loo, make sure you are not using the electronic shutter. I think the flash will only fire when using the mechanical shutter. 

I do miss the B&W pics, and still have my B&W lab. I tried B&W with my X100F, they were ok on the screen, maybe i should try to print them out to see if they look better. Do you still use Fujifilm cameras ?

X-Pro2 and GFX50r user here, but if we're posting cheaper alternatives, another option is the Foveon cameras. Not a perfect match, but I love shooting monochrome with them and plenty of examples out there.  

Aloe Vera blooming in back yard, along with Lupine .... X-S10 w/XC50-230 II