you need to do the "change of visa type" on Immigration. "Change" from a visa-exempt enry to an initial 90-days Non-Imm-O Retirement Visa. Application fee is 2000.- Baht. Proof of a minimum of 800,000 THB is needed. ATTENTION: the original police order says that you must prove that the money came from abroad. In your case you might have to circumvene this, as you said the money already is in your Thai bank account. Here are the requirements for the change, click onto number 9 which is your case
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