Plugged in not charging, processor speed drops when plugged in


May 23, 2016
Laptop says plugged in not charging, and processor speed changes from 1.6ghz to 0.5ghz when plugged in.
The laptop will turn on without battery but still run at 0.5ghz.
When using more force and twisting the charger will perform normally.
I have not dropped my laptop I done any harm to my charger as far as I know.
Recently the charger hasn't been working at all. I don't see any problem with charger or port, no bent parts or blockages or whatever could get in the way.
I have Dell Inspiron 5500 series, I'm using the charger that came with the laptop 8 months ago.
Thank you in advance :)
Edit: When turning on with charger, there is a message saying that the power type couldn't be determined, and that laptop performance will be changed.