Why does my iPhone xs max keep power cycling?

My iPhone XS Max keeps power cycling when after i plug it in to charge. It doesn’t do at all the time, but when it does it refuses to charge. When I plug it in, it will not flash green at the top and when i unlock the device and try to use it, it restarts until i unplug it. After i unplug it and it turns back on the wifi button in the command center is greyed out (unclickable). I have tried different cords/blocks, and the same result happens. I also think my charging port is clear of debris. Any idea on what this issue is?