PEP CELL RETURN POLICY

I won't ever buy a cell phone from PEP Cell again. I came to their store to buy a cell phone for my domestic worker only knowing that she's with Telkom. I had no clue that there were different phones that can receive only 3G or 4 G and in my ignorance I ask which of the 2 phones that can work with Telkom is the best. The lady showed me the "best" option and I thought I was good to go not knowing that my domestic worker has a 4G Sim card and this phone can only receive 3 G. Now they won't give me a refund as there is nothing technically wrong with the phone. I wrote an email only to get a response that I signed their terms and conditions stating that you can only return a phone if it has a technical fault. I went to an MTN store and they told me the they offer refunds if the customers network is not compatible. Surely the consumer's act protects one from this?