I had every problem one can have with trying to sign up for Apple Developer. I tried from multiple machines, browsers, different OS's, from work, vmware vm's etc. As soon as I turned off the Wifi on my iphone, and went back to the sign up page using only a cellular connection, the application worked exactly as one would expect: with no problem whatsoever. My device is managed is managed by AzureAD/M365 so, on wifi, I'm always connecting through a VPN. In fact in the upper left right corner of my iphone, one can see the string "VPN" next to the wifi radio strength indicator. As soon as I turned off wifi, the "VPN" string disappeared and I was able to finish the process with the flow and speed one would expect. My guess is that Apple is, and rightly so, applying conditional logic to the connection and connections via VPN should be suspect. A great many actors out there use multiple methods (which all boil down to "VPN") to access legitimate businesses and process with ill intent. Anyway give it a try: Use iphone Turn off Wifi THEN open browser (I think any browser will work at this point) Finish filling out Developer registration form (Apple has most of it pre-filled) Click purchase. It should process correctly. Accessing through the Developer App may work as well after steps 1-3 are complete but I did not try it that way.