Error converting with Currency Switcher on Booking/appointment Product

Dear Sir/Madam,

I have problems with Appointment product converting ( USD to MMK ) in the cart and check out page.
I use Booking plug in and multicurrency switcher included in your Package.

The product created simply without Booking plug in is fine.
Please notice the difference in the screen shots

https://www.havenofjoy.com/wp-content/uploads/2018/11/Screenshot-2018-11-20-21.46.21.png

https://www.havenofjoy.com/wp-content/uploads/2018/11/Screenshot-2018-11-20-21.48.16.png

https://www.havenofjoy.com/wp-content/uploads/2018/11/Screenshot-2018-11-20-21.46.43.png

Please kindly help me out with this issue as I need to launch my site very soon.

Regards,
Aung

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