@justme100 When you buy DTAC Tourist sim it remains as a Tourist sim for 14 days after which time if becomes 'Happy' which is the DTAC PAYG plan.
As you said in an earlier post you ordered the sim to be collected at the airport the 14 days would have started from the date of your order so now you are 'Happy'.
When you cross over the Cambodian border you will find that 'Happy' disappears and you will see DTAC again.
If you top up in Thai Baht before you enter Cambodia you can use that credit but if you need to top up while in Cambodia the credit dissapears when you reconnect to a Thai signal.
It is always worth topping up in 100Baht increments as every time you top up it extends the validity of the sim for 30 days up to a maximum of 400 days, useful if you are not planning to use the phone for many months. You can also register your sim online so that you can top up in Thai Baht at anytime. If you top up on line while in Cambodia you will not lose that credit when you return to Thailand. The maximum you can top up online using a foreign credit card is 1000Baht a month.
