st: Label already defined

[emanuele mazzini <madsoenistata@gmail.com>]

Dear Stata users,

I am currently merging two identical dataset containing exactly the
same variables so I re-labeled all of them in the second dataset, but
when it comes to the merge I got the following minor comment by Stata:

label varname already defined

Briefly, my question is: does this message (which I interpreted not to
be really an error message) is going to affect my results (i.e to
change the values of the variables for which this message is
displayed)?
It seems to be not this the case, but as it is quite important for me,
I'd be certain about this.

Thank you very much in advance for your time,

Regards,

Emanuele Mazzini.
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