The correct resolution here is that (TMCC) train numbers can only be 1-9. The units themselves can be double digits, but the lash-up ID itself must be a single digit. Directional lighting won't function correctly if you give them the same ID.
Example with my TMCC Santa Fe ABBA F3s - unique IDs are 20, 21, 22, 23
TR 1 (build) - add 20, 21, 22, 23 ( reverse the DIR on 23), hit build. Lights should flash and a horn sound. Address TR1 and start it up and this should work for you.
