Entity Reference Autofill overwrite only filled fields.

Hi guys,
I have my content with entity reference autofill with FIELD1 and FIELD2.
So, in my form, select a user and FIELD1 and FIELD2 automatically fill, but if change my user and select a user with FIELD1 filled and FIELD2 empty, the FIELD2 It has the value of the first and not overwrite the data.

Thanks for help me.

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Source: https://www.drupal.org/taxonomy/term/22/feed