AS bobby & guns mentioned, The only way to know the tiu's number is to count the red led blinks.
1 blinks means it tiu #1
2 blinks means it tiu #2 and so on. up to 5
Unfortunately dcs will allow us to add any tiu number to the remote whether it exists or not.
So count the blinks and make sure the proper tiu has been added to the remote, You may have to add, delete or edit the tiu under the tiu set up.
Maybe this will help for next time.... A tiu feature reset resets the tiu but the tiu retains it's ID number.