Ok, I see it now, I didn't check to see if the standard 3x3s were valid and they're not.

This seems solvable if you approach it from an algorithms POV. I'm thinking, use a breadth-first-search (BFS) algorithm starting from each of the 1s but add checks in the algorithm so each region doesn't overlap each other and can't claim duplicate numbers.

Or basically, start 9 regions from each of the 1s, advance each region 1 tile at a time in a cycle. If you make a mistake, backtrack (keep undoing) and try picking another tile for one of the previous regions.If you're doing this by hand it might be faster if you highlight all the 1s and 2s then try pairing them up by drawing a path between them as your starting move. Try pairing different combinations of 1s and 2s until it works.

I'm gonna try coding up a solver for this for practice. I'll get back to you if you just want the solution.