double skyrim.esm fix

[Chicauxerrus]

Hi, I wanted to know if there is a fix for the double skyrim.esm in the plugin.txt file issue because each times I add or remove a mod from the Nexus Mod Manager list it adds me it, one with a capital S and one without. I tried to remove them both separatly, see what happens if I remove all the mods from the list but nothing seems to work and it starting to really piss me off
After a research on google I found nothing, so if anyone could help me I would really appreciate it.

Thanks in advance.