You can come and go as you please , I’ve done some entry’s where I’ve only been in for 24 hours. In and out 14 times now since October last year no issues
You could make a purchase on a credit card , keep the paper receipts 🧾 like at McDonald’s or something then snip your corresponding section from your bank statement?
But also you should be able to change your grab name
I’m assuming you submitted a 6 month or 1 year Muay Thai course , they are asking what you will do once you finish the 6 month or 1 year course.
I would say that you will plan to book another soft power course after successful completion of the first one. And explain that booking 5 years worth of soft power courses doesn’t make sense