HI,
I solved my problem by disabling the verification of the certificate in the files:
/seahub/seahub/onlyoffice/settings.py
/seahub/thirdpart/requests-2.13.0-py2.6.egg/requests/sessions.py
/seahub/thirdpart/requests-2.13.0-py2.6.egg/requests/adapters.py
hoping it helps.
I noticed that simultaneous changes do not work when the file is shared and opened in editing at the same time by 2 users.
Does OnlyOffice integrated in Seafile allow this functioning as the onlyOffice original application?