Error With Epplus.dll when compile (Excel integration)

I am looking for a solution to integrate a tool allowing me to store data in the form of a table and export it in a format like excel to allow printing on paper. And to be able to modify the excel by hand to be able to import the data in unity.

I have to implement Epplus.dll which integrates a library allowing the access to the creation of excel spreadsheet and their backup. It works in editor but unfortunately when I try to compile my project I have an error (see attachment):

"Epplus is not allowed to be included"

Would you know how to make it included in the build, otherwise would you have a solution to my concerns if it does not include dependency on the final versions of unity?

Thank you in advance to all for the attention paid to my request