Is the problem a break, or a string height adjustment, or something else?
Previously I filed the nut to accomodate bigger string gauges for BEAD tuning. I returned to standard tuning and I had a buzz between my fretting hand and the nut on frets 6 to 8 on the E string.
I found a workaround thanks to this post. A cutter, a file, a strip of paper soaked in cyanoacrylate glue, a bit of meticulousness and here it goes again, as good as new.