Sean, were you able to find the solution to this? I'm seeing the same leaddb issues happening on my end. We're using Leandata to run our conversion, but are transitioning to Ringlead soon. I thought Ringlead would be the fix, but am distressed that you're having issues with Ringlead conversions as well.
Hi Matt,
I've been holding off bothering to reply to this thread. Yes, I found a solution. After my ticket spent months in Marketo's top tier support channels, they didn't have a solution. Well, not entirely true. They did, but it was not the actual solution. Here was there response.
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Hi Sean,
Thank you for your patience with this one. Our Engineering team looked into this case and found logs for the affected records. One such is below:
Logs show operations of data pull:
Lead Pull conversion SOQL:
Mar 28 17:42:31
Contact Record created in sfdc at:
sfdc_created_date: 2019-03-28 17:42:32
Contact pull-updates SOQL:
Mar 28 17:42:46
During a Lead to Contact conversion. When the standard conversion process is performed in SFDC, a new contact is created in SFDC and the data mapped between lead and contact is used to populate the fields of the contact in SFDC. The lead in turn becomes a "shell" of a lead. This conversion is pulled during the Pull Conversion operation in the sync. New contact records or contact updates are both pulled in the Contact Pull-Updates operation in the sync.
The lead was converted to a contact during the short window of time between the conversions were pulled and the start of the updates being pulled. The new contact was pulled over to Marketo by the pull-updates operation rather than the pull-conversions. Hence the creation of the new contact in Marketo - a duplicate. During the coming sync cycle after that, the pull-conversions operation merged the duplicates to complete the conversion.
Our engineers have confirmed that when this scenario occurs (a conversion happened in that small time gap), this behavior is expected to occur.
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See, I already knew this. That the API calls run in a specific order (there is a post on this somewhere) and that these got out of sync. But why? There is no answer to that, nor why my records caused this to occur dozens of times.
Well. I can now report that in our case, this was not due to RingLead. It was actually caused through the combination of having a lead validation rule in SF, plus a small setting enabled in SF.
In SF, navigate to Setup then search for "Lead Settings". Locate the "Require Validation for Converted Leads" checkbox and Disable this setting. This setting was causing field validation and workflows to execute on conversion, and this was the cause for breaking the sync API execution timing.
Prior to figuring this out, we also setup a great Marketo program that "captured" these irregular merge records. I highly recommend creating this as an operational program so that you stamp these errors as they occur so that you can clean them up.
Basically, the activity log registers two "Person is Created" records when this bug occurs. So you can capture that and add the record to a static list. My list currently has 18 people in it.
I wanted to let support try and come up with this solution or at least tell us to check that setting in SF, but unfortunately they didn't have many cases of this error occurring and never once pointed to this SF setting as a possible cause of the issue.
I feel pretty confident that if you disable that setting in SF, you two will see these issues cease to occur.
Funny thing that having that program to stamp them in place, one person (like 1 week ago) triggered the issue to reoccur. But I guess that's acceptable and is what you would consider "regular" occurrence of this de-sync timing issue.
I hope that this information helps others now and in the future. I lost maybe 40 hours to this issue.
Finally, shout out to @Veronica Holmes, it was an issue in Salesforce 
Nice work haha.
Cheers,
Sean
