Hi @isaiahstew89530
The adapter is going into self protect mode presumably because there a problem either with the DC-In jack e.g. internal short circuit perhaps or in the power distribution section of the motherboard.
Just as a check to make sure that it isn't a problem with the output cable of the adapter, plug the adapter into the power outlet ''only'' (do not plug into the PC) and check what happens to the green light if you firmly hold the adapter cable plug that is inserted into the PC and ''gently'' flex the cable where it exits from the back of the plug.
If the green light turns off and on as you flex the cable the problem is in the adapter cable. If not it is in the PC.
I can't find a schematic for the motherboard, but here's the [https://dl.dell.com/topicspdf/inspiron-24-5490-aio_service-manual_en-us.pdf|service manual] that will help, at least to gain access to the motherboard so that you can check if the [https://www.amazon.com/Zahara-Charging-Replacement-Inspiron-W24C001/dp/B09FL7Y8Y6|DC-In jack] (supplier example only) is OK i.e. use an Ohmmeter to check if there a short circuit connection between the +ve and -ve input legs of the jack and then prove whether it is in the jack or further into the motherboard - you have to unsolder the jack from the board to isolate it one way or the other or if there's anything obviously wrong on the motherboard e.g. burnt out or heat stressed components etc.