Hello I have a very big issue with my phone.. 3 days ago I left my charger at work, so when my phone completely discharged to 0%, I had to charge it overnight with a non-fast charge adapter I had at home.. it took all the night to charge to about 70%. Yesterday I brought back my original charger & cable and to my dismay fast charge isn't working anymore !!!! It is just like charging with the other adapter. Please help !
Check if cable can pass data. If can pass data, then problem lies elsewhere than phone and cable, which means fault is charger. Check if charger can fast charge other devices, if can, it means the problem comes from phone. Try and find which link of the chain is the problem
Try not to use third party charger if you can, it may be incompatible somehow after update / somehow it works in the past but now no more. It seems to be that ASUS implementation of QC is much more fragile and unstable than other device. If you check my previous post you'll know I once fried the phone due to power bank not exactly to spec. Now, the problem must lie in: incompatible charger / phone problem. Guarenteed cable is working
I don't know where the ASUS charger is, maybe at work. I have a Lenovo SC-42 charger at home. Test results same asus slow charge a Xiaomi Mi5, Mi8, Redmi Note 7 quick charge. My tests prove that ASUS has problem with QC.