iPhone 11 Charger not working

1. try another charger or charging using a computers usb port
2. try another cable or test the cable in another ios device

suppose it could be 

1. defect ac charger
2. defect cable
3. dirt or lint in the iphones connector when that happens to me i resolve it by removing it with a match or toothpick
4. a defect connector in the iphone