Currency symbol error

the currency symbol next to the cart icon in the header is stuck to one of the store’s currencies (SAR), right after i change the currency using the switcher it changes for a second then goes back to SAR, this only the symbol in the location i mentioned above, the actual prices and symbol next to prices are working fine so far.

how can this be fixed?
I have attached a screenshot showing the current chosen currency in the currency switcher and the currency symbol for SAR next to the cart icon in the header.

please not I have no coding knowledge at all, so the fixing steps must be simple otherwise they will be useless to me.

Thanks in advance