User Currency Selection Error

[KangLeian]

Is there somebody can help me where the setting or what should i do for my problem.

The problem is when i tried to change currency at user side it won't changed. I have 2 currency that been used. First, USD (default) and my local currency IDR. when i try to change the currency on user side from USD to IDR it won't change and just go back to USD. I've try to inspect element that USD has id=1 and IDR id=2. When i clicked to IDR it's return to USD and not changed. If there any solve issue like this please share the answer link here. thank you very much. 

note: I'm using payment gateway from my local country. It won't accept any other currencies for now. So, i need to used my local currencies. And i still need USD for compare rate.

[KangLeian]

Sorry and thanks, it's solved right now. I just figure that WHMCS only use default currency as payment. User side cannot change the currency it's just show that it has some currency that has been registered.

I've read 

Thanks to @brian! your sentences in that community is helpful.