Dmitry Did they scan it or just look at it? Normally they need to select Paysafecash in their system, then scan the barcode, and then take the money. Afterwards you just get a receipt, not a code or anything.
If you now have a Paysafecard that you don‘t need that‘s unfortunate. Maybe if you contact their support they can help you with that? Seems like it wasn‘t your fault but the partner store‘s staff that gave you the wrong product.