DeepSeek is the Chinese alternative to ChatGPT, cheaper, faster and more efficient for many tasks. However, if you have created a DeepSeek account in the app for iPhone and you used the account Apple, you will have a surprise when you want to log in from the browser. The DeepSeek authentication system with the account Apple not available in the browser.
A strange and unsolvable inconvenience, especially if you used the Hide My Mail feature from Apple, when you created your DeepSeek account. You cannot get a password or change your email address from the app on iPhone.

I also identified two other problems:
1. DeepSeek does not accept any email domain for registration.
2. The registration validation code never arrives at the @icloud.com email address.
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So, if you want to use the same DeepSeek account on the app on iPhone and in the browser (or in the app for Mac), the safest thing to do is to use Google authentication or create a new account with an email address and password.