Pillow top mattress issues

We currently have a pocket sprung mattress with a topper attached (pillowtop mattress I believe?)

Bought 5 years ago which has given both me and my husband backache, I have shoulder and hip pain in the night causing me sleepless nights and waking up like I have been run over.

I am 10:11 and 5/8 my husband is 14 stone and 6 ft .

We are both side sleepers.

What mattress would you advise, please?