X00TD charging issue

Hello all,
My friend has an Asus Zenfone Max Pro M1 X00TD, and I helped him to install /e/. He likes it a lot and he has an experience about charging phone. The charging mode keeps swapping randomly, between “slow charging”, “fast charging” and the normal charging mode. Due to this, the capacity is about 30 % less than the slow normal charging method. We tried different chargers but the same result, so he only charges by USB connected to PC or laptop.
He uses the latest /e/ version for X00TD.
Did anyone experience such issue? Thank you in advance for any reply.

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