Yes I purchased a waterpik flosser on Black Friday 2018? And three week later my mother got me a much better flosser / toothbrush and now I need to return the unopened waterpik flosser but, I’ve lost the reciept

This is an old question but for future reference if you provided a phone number to a sales associate or consultant we can lookup your entire purchase history with that number. The stores return policy is 14 days or 2 weeks, but if the box was never opened they will most likely take it but also charge a restocking fee.

They will likely not accept a return without a receipt but may let you exchange the item.

Sorry but, You may have to give this as a gift to someone at a later date.