unique sourcetype appends a -2

[lbrhyne]

Hello, We are using inputs.conf and props.conf to ingest a flat csv file. The issue we are having is the sourcetype name is appending a -2 to the sourcetype even though it is a unique name. Example: sourcetype=sourcetypename | results sourcetypename-2

#inputs.conf
[monitor://C:\Import\sample.csv]
index= test 
sourcetype= sourcetypename

#props.conf 
[sourcetypename] 
FIELD_DELIMITER=, 
CHECK_FOR_HEADER = true 
HEADER_MODE = firstline

 Any help would be appreciated!