What should I do if my Thai DTV interview is scheduled when I will be out of the country?

I've recently applied for a DTV from Singapore. I'm a Singapore citizen.

I applied under the freelance/digital nomad route.

I have income from my online and in-person (only in Singapore, fly in couple of times a year) work, but the rest is mostly from passive income (rental and dividends)

My big issue is with the interview. I applied on 29 September, and I'm flying out of the country to Korea on the 20th of October. I assumed that I would be able to defer the interview should it be scheduled after I leave, to after I come back from Korea but I read somewhere that one has to reschedule their interview within 7 days of the requested interview day/time or the application gets rejected.

Does anyone else have such an experience before? I have another 18 days left for additional documents/interview, and I know that every country is different. Just feeling a little anxious and wanted to get some perspectives. Losing $500 is a lot of money.