After doing a lot of things as:

-          Rollback to 0.12.1

-          Edit report.py

-          Create system parameters for report.url and similar

Without any succeded, finally I found where the problem were focused.

I was wondering why with the same server and files reports were working ok in a totally clean database, so I managed that it can be only a problem related to “odoo_citi” database. After Googling some github community messages a found an user with the same problem with header and footer not printing at PDFs and he solved cleaning the filestore.

Seems that Odoo stores some files used to generate reports into the DB filestore as a “cache”, if the generation of those files failed sometime they remain stored as is. Cleaning that files from filestore forces Odoo to render them again and… voila!

Ref: https://github.com/odoo/odoo/issues/1105