Tablet worse experience

I bought a tablet at Ackerman's in Feb 2020, March we had lockdown, something happened to the screen of my fone and it just became Black, I took the fone in April 2020 they told me me to keep it they will call me when to bring it as it's lockdown and the people who fix the fones are closed , I kept the fone now it's may nobody has called me I'm coming from the store now and they need the receipt, but the receipt no longer has any printing on it it's blank as it was in the purse the whole time,they can't take back the fone cos I don't have a receipt, I mean I took this on account, surely u guys must have a duplicate slip cos u take the 1 and give the clients theirs. Pls explain how I'm supposed to pay for a phone that is not working after empty promises