Refused to accept tablet for repaot

Before Christmas 2017, I purchased a Mecer tablet. It was sluggish and kept on crashing. Because of all the pubic holidays, I miscalculated when to take it in, missing a refund by 1 day. They sent it in for repair.

The supplier replaced the unit, but took a week and a half to get it back to me.

I had the tablet for just over 2 days, when it would not reboot. I took it back to Matrix, who in turn explained that I could not get a refund and the unit must be returned to the supplier, which it was.

After a week, I called to follow up on the tablet. They said they'd get back to me. The following Tuesday, they phoned to say the supplier said the tablet was ready to be collected. It took them from Tuesday to Saturday to call me to collect from them.

I've had the tablet for just over 3 days and exactly the same fault occurred. I returned it to matrix this morning. When asked if I tried anything else, I said I tried to restore it to factory settings. The manager now said the warranty could be void because of that. This is odd, because the Samsung manual explains how to do this. She then accused me of modifying the software, which is totally false.

She then said that they couldn't accept the unit in for repair without the original packaging. This is odd, because the first time it went in for repair they didn't ask for it. Personally I think she's being petty.