How do I credit maxx

[ZoomerSpicoid415]

I’m 20, credit score is 750 flat

Have 3 capital one cards, 2 Amex , 1 Chase

I been stuck at 750 since forever it hasn’t changed since maybe June of 2023

I called Chase to put my limit up and I was told no and the Amex said in 3 months I’ll be eligible

Trying to get 0% introductory interest and debtmaxx