Crepey neck

[Denimdreams]

55, face not too bad but have suddenly developed a crepey neck .
Is it too many creams -tried Prai - rubbish,moisturisers etc
It's sort of fluidy in the top layers where you would expect it to be firm.
All suggestions welcome before I invest in a ton of scarves and polo necks.

Just to add the rest of me is in quite good nick.
Slim, exercise, no yo yo weight, body skin is firm including upper arms etc
Factor 50 everyday no alcohol/ cigarettes

Hate to say it but the only thing that’s worked for me is skin booster injections. 3 of them over 6 weeks. Looks great but cost me £300.

What is the skin booster?