How to charge faster on Laptop's USB 3.0 port (only 500ma instead of 1000-1800ma)

On rare cases I've seen my LG G4 charging so fast on USB 3.0 port hub, the ampere app shows max current as 700 to 1800ma !!
Now tried different modes like Charge Phone, MTP Mode, PTP Mode etc. phone only charging at speed of max 500ma :mad:

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