fit with (something)
1. To correspond to or compliment something well. I'm sorry, but that paint color just doesn't fit with the calming aesthetic I want for the yoga studio.
2. To give someone the necessary items or equipment to do something. In this usage, a noun or pronoun is used between "fit" and "with." The coach knew it was my first year playing hockey, so he fit me with the other gear I needed.
fit with something
to harmonize with something; to go well with something. Do you think that your behavior fits with the occasion? This coat doesn't fit with these slacks.