dissector frame buffer is not getting refreshed

Hello I have added a .CSV parser and a dissector. It is observed that if my .CSV file is opened as the first file in wireshark, tvb buffer contents is proper.

But if an other file is opened first and then my .CSV file is opened then packet dump is of the previous data. This is not the behaviour with other sample files.

Can anyone help me to resolve my issue?

thanks in advance krithiga