Hi @耀駿 施
As per my test, the same endpoint is working fine on my end. One of the possible reason for getting this 'Unable to find target address' error message could be not using work/school account. Create Team API does not currently support Microsoft Personal Accounts.
Also make sure, valid Office365 license is there for a work/school account.
Generally 500 error usually means there is something wrong with the server. You could wait for some time then test again.
Refer to this error status codes to know more.
Hope this helps.
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