Toothbrush heads for Fairywill electric toothbrush (Hampton Magna CV35)

I have 6 brand new, unopened heads for a Fairywill P11 electric toothbrush.
I bought a box of 8 but the toothbrush gave out just after I fitted the second one and will no longer recharge (I have had it for several years). I’m very pleased with the toothbrush and would have bought another but they no longer seem to sell this model in the UK so I bought a different one and these heads don’t fit.