I want my phone back or my refund

I sent my phone back to Take a lot after it started freezing and everytime I had to reboot the phone everytime, they told me that the supplier tested the phone and nothing is wrong with it and they were going to return it, now it has been close to 3 weeks waiting for my phone, I send a lot of emails and they always reply saying we apologise for the delay please be patient, am sick and tired with their service I need my refund