Horrible service from Sealy

We bought a Sealy Tetra Firm base set from The Mattress King in Somerset West on 7 March 2022 and was told that this bed has a 2 year guarantee and a 10 year warranty. This was definitely not the cheapest option. After using the bed for around six months, I started getting extreme backpain during the night. After a while my husband also started complaining of backpain. We then inspected the mattress and came to the conclusion that certain areas pop back up better that others> There also appeared to be areas where the mattress seemed to have collapsed. We send a video and pictures to Mattress King and was told that Sealy had to come and do an inspection to determine what was wrong, but that Sealy was closed for December holidays Sealy opened on the 16th of January, after asking them repeatedly to come out, someone inspected the bed on 30 January. After following up again today (06 Feb) I was told that they found nothing wrong with the mattress and wasn't planning on doing anything about it. We didn't select this bed randomly. Mattress King did a computer simulation to determine which bed would fit our needs best and this one was suggested. Due to this horrible after sales service, I will never buy a Sealy again!