HP Omen Ryzen 7 7840HS + RTX 4050 suddenly overheating

I've been using my HP Omen for \~11 months, and temperatures were previously normal (Valorant: 75–85°C, Spider-Man/Miles Morales: <80°C).

Recently, Valorant reaches 95–99°C, while demanding games push the CPU to \~100°C. Yesterday, Spider-Man 2 even gave me an RTX 4050 overheating warning, followed by a game freeze and another overheating warning.

I had it cleaned at an HP World store in July. The technician cleaned the fans/heatsink and replaced the CPU/GPU paste with a golden/yellowish paste. I don't know what paste was used, and some other thermal material was left untouched.

My warranty expired in August, and I don't want to open it myself.

Could this be bad thermal paste/application, heatsink mounting, thermal pads, or a fan/heatsink issue?

I'll attach HWiNFO temperature/wattage screenshots and photos of the cooling system.

Photo details:

All pics show the laptop’s cooling system and HWiNFO data. The 2nd and 3rd pics show old white thermal material and other copper/heatsink contact areas that weren't cleaned or repasted. The 4th pic shows the technician applying a golden/yellowish thermal paste to the CPU/GPU, which I suspect may be cheap. The 1st and last pics show the CPU temperatures and wattage from HWiNFO.

What should I check first?

Why is this happening?