You flashed the recent firmware from bitmain which is a one-way street, you will need to use the recovery file and an SDcard to revert back to an older version, you will need to find the T9 recovery firmware which is no where to be found, but I believe you can use the T9+ files since they both use the same control board, this very version is what we use on the S9/S9i and S9j as well.