Extender faulty

Xfinity technician came out to the house stated the extender was garbage and I should get another one or a refund. Noyone has helped or offered credit on our bill for the price of the extender that I was told to buy for 120.00 from an xfinity store. No receipt no return. Had it for a month and still no internet on my property in the back part if my home. 

Hello @user_w5co8n, Xfinity Wi-Fi Extenders are subject to the Comcast 30-day money-back guarantee and may be returned for a full refund within 30 days of the original purchase date. Additionally, Xfinity Wi-Fi Extenders are subject to a limited warranty and may be replaced within one year from the date of purchase if the issue with the device is covered under the hardware warranty. To return or exchange the Wi-Fi extender, you can fill out this online form here. If you need help completing the form we would be glad to assist.