You probably need to use a PD charger (power delivery). If you have android USB C chargers, use ones that phones have “fast charging” or USB c chargers for laptops. The key here is that the wattage is too low on the phone chargers you’re using. I can charge my square terminals slowly with 10w chargers, the standard 5w from a computer won’t do. Shoot for 18w or above to use less power than the charging rate. Good luck!
It unfortunately has made me lower my expectations on candidate attendance to the point I schedule them closer together and slightly overlapping at times to make sure the hours I set aside for interviews are allocated efficiently