FediTips has moved!Hmm... that's weird.
Just tried to find similar bugs on Mastodon github but nothing that fitted this exactly...
Did you do all the transfer steps in the order listed on the guide? (https://fedi.tips/transferring-your-mastodon-account-to-another-server/)
You have to first do the alias on the new account and then wait some time for the new account's server to set up the alias. (Steps 1, 2 and 3 on the guide.)
After you've waited for some time, you can move on to step 4 on the old server.
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