brush converted to mesh has 2 materials now

i don’t get how this happened, i was setting my brushes close to each other by snapping to grid in order to make corners look perfectly alined, but apparently didn’t work, cause now i have this, oh forgot to mention that i put a transluscent material so you can see what is going on


bump and solved ! i managed to make it a one single mesh, just converted a second building and this one worked well