If the Tenant/s have signed the lease agreement and you have not received the notification for you to sign and complete, it is likely they haven't "FLK'ed it back" which is the final step on their end.
To check this, please follow the below steps:
Click on the agreement in Sent for signing tab then select Audit trail in the top right corner:
You will then need to scroll down the page and look for a green tick next to 'sent back to the agent'.
If this is missing, it means the Tenant has not completed the final step, and you can contact them directly to do so.