Adding a Currency in MS Dynamics POS

Freaky

Good Morning,

I want to use GMD(Gambian Dalasis) as the currency in POS, I notice that the GMD is not in the regional settings list in the control panel so I choose Dollard and modifyed it.

When I come under POS, everything is ok but when I add a new Item I'm having an error message:

The value entered is not a valid currency value
The value must be in the regional currency format that is selected in the control panel
The previous value will be used

Any ideas?

Thanks in advance