Ridiculous return policy

I purchased a ADSL router/Modem from Matrix Warehouse in Three Rivers

I wanted to return the device, never been used as we opted to go with Telkom LTE package as our ADSL line was taking to long to repair

I wanted to return the Modem and the denied it because it was 2 days over the 7 days return policy

The modem has not been used, in its original packaging, undamaged at all but still im denied

i believe this to be completely unfair and irrational, and to top it off there excuses are completely ridiculous