There is another way of looking at this, that is to have two numbers on one phone contract, which means you pay one bill for two numbers. You will numbers given two sims as outlined by the other replies. AIS and probably the other big suppliers can provide this.
have you tried it recently? It's a Thai banking requirement, that over 50kthb or 200kthb in 24 hours requires face ID on transfer on an app, the pictures needs to be done at the bank.
this is getting boring, my government pension is 13 times a year and is not enough, my private pension can be paid every 3, 6, and 12 months. So unless I take the lump sum and then send an additional monthly payment it won't work, not only that it will be more effort and cost and more explaining at the immigration office, not very appealing.