After Connected Campaigns is enabled in Account Engagement, any new campaigns created in Salesforce after the enablement of it, will sync automatically to Account Engagement as a syncing connected campaign. However, existing Salesforce campaigns already created prior to enablement of Connected Campaigns do not automatically sync and will only sync to Account Engagement as a Connected Campaign, if the last modified timestamp is updated on it which then triggers a campaign sync to Account Engagement.
Firstly, you would have to ensure Connected Campaigns has been fully enabled in Account Engagement along with ensuring that those existing Salesforce campaigns are eligible to sync as a Connected Campaign by having the relevant record type enabled for connection and it being created within the specified timeframe if you have limited the campaign creation by date. To check these things, it’s as follows on the Connected Campaigns settings page in Account Engagement:
If all the above three things in relation to having the relevant Connected Campaign settings configured to allow existing Salesforce campaigns to sync as a Connected Campaign have been done, then to trigger a sync of an existing Salesforce campaign to Account Engagement, the last modified timestamp has to be updated on it which can be done as follows:
Configuring Connected Campaigns Recommended Order of Operations: https://help.salesforce.com/s/articleView?id=000380898&type=1
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