Please Check the plug port via a torch to see if there is any buikd up of debris.
Sometimes when a phone is not behaving after an update some generic troubleshooting tips are …
1. Put the phone in Safe Mode which disables your downloaded app's but let's your stock app's keep working. If the issues stop then this highlights a downloaded app as the possible issue. Come out of Safe Mode and start deleting your most recent downloaded app's one at a time until it stops. https://www.samsung.com/uk/support/mobile-devices/how-to-start-my-galaxy-device-in-safe-mode/
2. Clear your phone's System Cache Files by turning your phone Off and then from a set series of button presses go into the phone's System Files and clear the cache. No information is lost this way. You may need to insert your headphones or hook upto a computer with your data cable to get to this menu on the phone.
If it's the charging port then a Samsung Experience Store or Samsung Service Centre can take a look but if the damage is user caused then expect a repair bill.
I wish you all the best with this.
Daily Driver > Samsung Galaxy s²² Ultra 256Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help.
@ant21: If you head to Settings > Device Care > Battery > Charging, is Fast Charging toggled on? If it is, try powering off the phone before connecting to your charger to see if you notice an improvement. If the issue persists, open the Samsung Members app > Get Help > Interactive Checks > USB, and follow the on screen prompts to see if this returns any errors.