Livestainable Complaint

I purchased 2 Lithium Batteries from LiveStainable at end of November. They arrived in December, but my Electrician was on leave for the month, so I was not aware that you could not mix Lithium with GEL Batteries for Solar purposes. Immediately I discovered this I contacted this Company who refused to accept them back as it was past their 15-day return policy. After a lot of aggravation, they agreed. These were brand new, still boxed and never used. We sent them back via Courier and they received them a week ago. They never answer phones and do not respond to emails. I finally got somebody on WhatsApp yesterday, as I said I was looking for batteries and they responded. I demanded the return of my money and they said there was nobody in the office who could authorise and make payment. I told them to get the owners who are named Coetzee to make payment and they said they are also on leave In my opinion to hold back a refund of this nature with no genuine reason, constitutes Reckless Trading. Just because somebody goes on leave, the entire Company structure should not fall. There should be a responsible person in place, or contact should be able to be made with a person authorised to make payments/refunds. There is no excuse! After all this is quite a substantial sum of money. There is no correspondence from them. It is nearly impossible to contact anyone, other than tricking them into thinking that I wish to make a purchase. That was the only way I managed to contact somebody and have been permanently on WhatsApp since yesterday complaining and moaning. I should not have to go through this, it is extremely stressful at my age of 75, having this problem. If they have done this to me, they have probably done this to others. This type of trading needs to be stopped in its tracks.