V12 Request Raw Material: TypeError: unsupported operand type(s) for -: 'float' and 'NoneType'

Does anyone know the cause of this error? I encountered this when I was trying to Request Raw Material via Sales Order.

Report it on Github

Just reported: https://github.com/frappe/erpnext/issues/19397

I know it is kinda late as I was very busy lately.