I am getting the following error: There is a problem with task “Update User

I am getting the following error:
There is a problem with task “Update User Profile” in the process “xxx”. The selected user is invalid.
But my user is:
1. Active
2. Responding to the user() function
3. The 'Update User Profile' node is working correctly in a test process.

Can any one explain why I am getting this error?
Thanks...

OriginalPostID-80125

OriginalPostID-80125

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