Linksys 1900ac problem with quality of internet over wifi

Hi , I dont know what happened with my cfg , but after last update I start getting problem with my internet over wifi cfg
So we talk about linksys 1900AC with last firmware 19.07.7 r11306
My network has 2 ISP x 1Gbps each; plugged into cisco 345p ( multi wan used)
I create 6 vlans : vlan1 is default router vlan, then the rest to export into 1900AC using 1 cable
Into 1900AC I create 6vlans
I will add pictures

What I want to achieve is to have 1 2,4Ghz wifi for IOT, then on 5Ghz to have one for Guest, one for multimedia, then one for laptops and phones

So I dont know if is my config or is about firmware . When I do a speedtest is good and nice like 300-500Mpbs , but on browsing or youtube etc stack , lagg, not working etc

Thank you for any information