Coupons not showing up

Iv gotten two notifications for coupons that two separate sellers sent me yesterday and this morning but when I open the app or click the notification the coupon doesn’t show up and the notification disappears, it’s not in the coupon, sales sections and it’s not showing on the sellers items directly or in my cart either. I feel really weird messaging the seller about it but if they meant to actually send me the coupon it would be nice to have it. This is also not the first time this has happened to me.