trying to test app on another device

Hi - I borrowed an iPad mini from work today to test my app on it. I added this device in my development profile on the apple developer website. However I can’t install any of my apps on it, including the one I’m developing (the “automatically install new apps” checkbox is greyed out).

I’m assuming I would need to completely erase and reset the device, as it’s associated with another apple ID, and then associate it with my own ID. Can anyone confirm this for me?

thx in advance,

David