Ah ok, but different to my issue, which is build up of hard skin/blister around the edge (side and behind) of the ball, which then hardens and causes it to continue to blister when running
I have also been doing some glute exercises which has helped. Read a blog post somewhere were someone with ball of foot blistering essentially solved it by really working on the glutes. Apparently weak glute causes you to roll the foot (maybe from out to in?) and its that repeated rolling and friction that causes which causes the blistering
Again, not sure if that sounds familiar to you? I'm also not an expert!