I had the same issue at PlayStation, but with my own .com domain. I didn’t receive any validation emails on there, but after changing it to my gmail it was fine

I had the same issue at PlayStation, but with my own .com domain. I didn’t receive any validation emails on there, but after changing it to my gmail it was fine. Watch out when trying to change it back to your custom domain. I tried that and was locked out of my account. Had to call PlayStation support to change it back.