CVS review: Not receiving an email receipt so now I can't exchange hearing aid batteries

On 12/31/2020 went to CVS 3915 Durand Ave, Racine WI. to pick up my prescription of NovoLog and saw hearing aid batteries on sale so I pick some up. Went to pharmacy and picked up prescription and paid for batteries also. Teller handed me my bag and I asked where is receipt and she said it will be emailed. Said ok. Well got home and saw they were the wrong batteries. Checked email and there is no receipt. Went back to store and teller said I need to come back when manager was available. Asked when and was told Monday 11:00 am to 1:00 pm. Went to store today around 11:00 am and was told no manager was there. Asked when he would be there. Said can't give out his schedule. Well how do I know when to come back? Was told around 3 hours. Came back and talked to manager and was told without receipt there was not much he could do. He could give me a 15 dollar store credit. I said I spent 70 dollars on batteries and never received a email isn't my fault. I was there and they have to be able to look up receipt to see I purchased these. I just want to exchange them. Then I just cussed all the way out of the store.