if you are indeed in Phuket (which Patong is a part) you need to call the Phuket immigration office directly. They should be able to tell you what to do,
IF I was to guess, I'd say because you're on a 'long term' extension you are NOT covered on the amnesty program and you're gonna hafta get the documents from your school saying you're still studying so you can extend your stamp OR that you are no longer studying so you can cancel your current extension and then you would be covered by the amnesty.
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