I am trying to sum "Order Qty" from a table in my Access database where "Material group name" equals "Generic Rx" through a Sum if formula

I am using:

```
Gen Ordered: SUM(IIF([Material group Name]=(Generic Rx).[Order Qty],0)

```

but I am getting an invalid syntax error at the Generic Rx expression

"Generic Rx" is value within the "Material group name" column

what is the best way to go about this? Thanks