Disappointing Customer Service

On the 24/04/2020 i purchased a remote at Pick n Pay Wonderpark and when I got home it was not the correct one.I went to Wonderpark many times to exchange it however with the long qeues i returned with it.Today i went again and was able to get through ,spoke to Kabelo who advised that they cant exchange it as i bought it 14 days ago and that because it has been opened they cant help me.I advised him that no-one told me about the 14 days rule and its not stated on their till slip.He kept on asking me who assisted me on that day and told me that no one assisted me on that day.He then said that i should come back the following day to speak to his HOD as he cannot exchange it .So now i have to spend another money on petrol to come speak to his HOD regarding negligence on their part.Apparently there was supposed to be someone to assist when i purchased the remote to advise me properly but there was no one on that day to advise me regarding the 14 day rule.I returned home with the remote. Should i be pernalised for staff that was not available to assist me on that day, the fact that they cant take it back because it's opened is really absurd as i had to test it to check if its working or not.The other day I bought electricity at their store and when i got home the token was used, i contacted them and was advised that it was not their fault as Tshwane Municipality should be held accountable and that i need to contact them.I contacted the Municipality with my airtime and was assisted. So should I be accountable to the mistake that there was no one to assit me when I purchased the remote and for him not to even say he will escalate it for me and that i need to come back is just not on.Am so dissapointed to think that i do all my shopping there and pay my bills there and yet no customer service was displayed.Its really sad that as a customer i need to do the run around everytime someone messes up. Maybe your staff need to swap and go to Pick n Pay Menlyn and all the other white suburbs to see how the staff there display their good customer service s****s as the service is different fron the one I experienced in Wonderpark.