Letter "C" in the data when I convert HST files

Hello,
the letter c appears in all data records when the HST file is converted.
Attached is an example:

9/01/2020C00:00:01C 6.491C 1035.590C 2.107C 2.590C 3.250C 1.431C 0.196C 12.592C -0.186C 6.472C 10.522C 7.704C 12.001C 0.000C 0.000C 77.807C 78.041C 0.011C 17.445C 0.000C 0.000C 0.004C 5.000
09/01/2020C00:00:02C 6.491C 1035.518C 2.107C 2.592C 3.251C 1.430C 0.196C 12.592C -0.186C 6.472C 10.524C 7.905C 12.003C 0.000C 0.000C 77.807C 78.062C


Someone knows why
Thanks
Aaron