@saurabh a​ The attributes you map between Intercom and Salesforce are synced when they change in either system. When the change occurs in Intercom, the sync to Salesforce is triggered immediately, while Salesforce is checked every 5 minutes to determine if there are changes to sync to Intercom. Here is an article on that. Likewise you can sync data between accounts in Salesforce and companies in Intercom. Currently you can only sync business accounts, not person accounts. More details on this can be found in this article

Hey @saurabh a​! Daniel from Customer Support Engineering here 🔧 

Could you contact us via our Messenger regarding this issue? There isn't a one-solution-fits-all answer when it comes to Salesforce issues, so it would be best if you could contact us directly, along with as much detail as possible regarding the issue (when it happened, what isn't syncing, error codes, etc.).

Thanks! 😁