Leads generation automation tools/problems

Leads generation automation tools/problems

Hi!
I've been struggling to fully automate the leads generation process from Facebook Leads Ads.
As far as I know, it is possible to push all the generated leads from Facebook forms into Zoho CRM using Zoho Social integration. However the problem I am facing is that it is possible only in the case of NEW LEAD or UPDATE (existing) LEAD. There is no possibility (or I haven't found it) to UPDATE (existing) CONTACT if there is a case. I understand that it is because these are two different modules, however I was wondering how do you deal with this issue? Our Contacts module contains thousands of records, so in every campaign/form that we launch there is around 10-20% of existing Contacts, that are not being automatically pushed/updated in Zoho CRM, nor I get notified of it, so they are entirely ignored. I've been checking for some external integration platforms, but the issue is the same - I am not able to "sort" through both of the modules, in order to create or update leads or contacts (depending on the case).
Does any one face the same problem?