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🤔 You should create a password for Keychain app and log in to it first. Have you done this?..

Yes
I told you the sign in button is not clickable. See

IMG_2405.jpeg

The button will work as soon as you solve the thing with KeyChain. So there is advice in the screenshot to add an extension to your browser. If this doesn't work, it might be that your phone is too old or it might be something else.

Yea
My question is how do I add the keychain extension to my phone browser? I use iPhone