a friend of my son was stopped too, had a new TR from Phnom Penh, money in the bank, but no cash, they send him back to Phnom Penh. I do not understand the world anymore. Now he will try at another border.
most likely the OP is on extension of stay based on retirement. A retirement visa does not exist. Do the TM30 thing first, than 90day reporting. And before the extension expires do a timely renewal.
legally there is no limit, however after a couple of times you will be grilled and warned to get a proper visa. BTW it is not Tourist visa it is the visa waiver program you are asking about.
I removed a reference to VOA, as Spanish the OP is entitled to visa exempt or visa waiver and will get 30 days, however as a newcomer Thai Immigration, in most cases, will not ask for the 3 proofs. But I am sure that the airline check in staff will ask you to show an onward travel ticket.
create an yahoo or outlook account, than you get immedate the reply, me too have no idea why just gmail accounts take average 6=8hours. i guess the developer likes to piss off people . it is a nuiance and has been brought forward on many occasions to rtev.
as far as I can see only 2 very minor things which are not completely covered, but overall perfect, why the relevant agencies never update their webpages, like the MFA is a disgrace.