Modem arrived damage and they will not replace - horrific service

We received the new sim card modem from Talkom and within 2 days it didn't work. After a lot of messaging back and forth during lockdown I dropped it off at Canal Walk branch. They phoned today to advise we damaged it, it is not under warranty and therefore cannot be repaired or replaced. I cannot get through to the lady that phoned that it was obviously damaged in transit to our home and has never worked properly. I now have no modem, yet am charged full price for a modem that arrived with me in a damaged condition. Disgusted at this service. How can I be to blame for a damaged modem Talkom sent me?