These are tricky and I have experienced the same angst with my Thai relatives and friends I have assisted ! Providing you have time, I would be tempted to leave it to the airport to sort out.

Note that even if it is OK departing Thailand as is, other jurisdictions may be more strict...so getting it fixed may be a good idea... No doubt others will be able to provide advice based on experience (I haven’t had a ‘fail’ so far).

I have never booked a ticket whilst logged in to my ROP account. Does it actually work and pre-populate data fields for you?!