Indicates that the heat on the CPU is not transferred to the radiator.

It is possible that the spring or fastener that fixes the heat sink is aging or deformed.

So that the CPU and the radiator can not be closely attached,

I suggest you check whether your fan and heat sink are closely attached.

Gently shake the heat sink by hand, and there should be no looseness and shaking.

You can also gently press the heat sink when the fan is running, so that the heat sink fits the CPU better.

See if the heat will be transferred to the heat sink. If so, your fan heat sink is not fixed on the CPU.

Too thick silica gel will also affect heat transfer. When applying it again, you should dry the original silica gel first, as long as it is applied to the nail thickness.