if they use AIS they only have to provide the receipt from the company. I had this problem last month and I went to my banks with the receipt to have it fixed in time. Kasikorn bank has warned the account holders about this 3 months ago
go to the Bank, give them your new number. They have a system there linked with AIS and other telephone companies where they can check wether your phone number associated with mobile banking is in your name, or not
they would make it a lot easier for them and for everyone else if they gave a fixed number of days per year that you can spend in the country as a tourist. How the policy stands now it is absolutely irrational since some people get punished for nothing while serial border hoppers are still allowed to operate with impunity
i don’t plan on getting a long term visa, as far as I am concerned 4 months should not cause any problems. I usually spend 2-3 months outside the country anyway. A lot of Thai tourism is people coming back. If they were to start systematically denying entry to people like me they would really screw up. On the other hand I am not surprised that they deny border runners. I have not done a single border run since 2001 when I first visited the country
I will give an advice as someone who spends 4-5 months a year in Thailand on tourist visas, or exemptions, and who at one time had an ED visa (which has not attracted any attention from immigration). Don’t attempt more than two trips a year without a long term visa, 4-5 months is possible, but more is risky.
I use UPS a lot in Thailand, very good customer service. Try contacting them by phone, or walking in at the headquarters in Soi Lasalle, Bangkok to get information.
If you do manage to get another ED visa it will not be for beginner classes.
I had the initial 3 months of ED visa and left the country for an emergency and when I came back 2 years ago I tried to study at another school and I had to provide transcripts from my first school and I was told that I would start from an advanced class, not beginner due to already studying for 3 months