Galaxy note 9 fast charging problem

[bennydadon]

lately, somewhere after update to one ui 2.0 I started to have some problems with the fast charging.
as for now, the fast charging won't work unless it plugged to type C port in my PC that supporting QC3, and even that for like 1 minute max and that shorting my WHOLE pc's USB ports.
tried many bricks and cable supporting QC3 though the phone supports QC2, and nothing sadly made any change, tried as well on using the original brick and cable and still the same.
I've also been trying for like a week to clean the port with cotton and 70% alcohol and nothing changed
I tried to measure the Amps coming from the charger and got like 2 Amps max, although I remember when the Fast Charging did work, it gave like 3.3 Amps(all measured by ampere app)
I'm thinking it may be the port itself, but not sure about it
what do you think?
any help will be appreciated

Edit: I tried to wipe cache and charging in safe mode

 

[iceepyon]

Try wiping the Cache Partition in Recovery Mode.

 

[bennydadon]

Try wiping the Cache Partition in Recovery Mode.

I did that and even in safe mode.
Post edited and these stuff added

 

[TokedUp]

This is a well known issue with all Samsung phones. They use the cheapest USB connectors on the market and they short out very easily. I lost fast charging over a year ago when my phone said the port was wet even though the phone had never been anywhere close to any water ever. The only way to get it back is to replace the USB port. With the phone being so old its not even worth the money to fix. Same ship happened to my wife's S9+ . I'm not buying another Samsung phone.

 

[kfreels]

Thanks. I can see how a cheap port could be the problem. I've had this problem with my note 9 since day one. I can plug in a brand new cable that works great with somebody else's phone into a Samsung charger and randomly it will max out at around 750 ma or 1040, 1425, or up to 2275. This is even when the phone is at less than 20 percent, and the phone is not warm at all. I have wondered if a faulty temperature sensor has been to blame.....
What's odd is that i can take it off a QC or Samsung charger, stick it on a battery pack and it hops right up to 1200. Got a temperature sensor app and all is around 120 degrees F which I'm pretty sure is normal.

 

[blackhawk]

Do Not use 70% isopropyl alcohol on electronics, it's 30% water
Only use anhydrous isopropyl ie 99%

Use a OEM fast charging brick and cable. They're cheap, $20 for a Samsung 20w brick and cable.
Erratic fast charging and a rapid drop in battery capacity may indicate a battery failure.
Any case bulging is a battery failure; replace asap.