There is not enough information for us to address your issue.
Can you please clarify in which Talend version/edition you are? Is there any error message? Trouble screenshots will be helpful for us to address your issue.
if you were a free user, all your projects were only saved locally on your machine, never in the cloud.
When you have tried to migrate from Restlet client to API Tester, you must have seen that a window popped up to backup your projects.
If you saved this backup, you can now re-import everything in Talend API Tester.
I hope this helps.
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