Why is my CSV index renaming the first field to some random field name?

[bhupalbobbadi]

Couple of my CSV indexes in Splunk (UF to Indexers) have been creating/renaming the first field in CSV with special prefixes for example Id is becoming xE2_x81, and ReportID becoming  xE2_x81ReportID or  xE2_x90ReportID, and it is changing to new name automatically after few days. Any help in fixing is appreciated. Thanks in advance. 

[diogofgm]

It seems that you might have some hidden characters in your original data. Open the file with e.g. VS Code and enable the the render control characters in the settings to check if there are hidden characters there.