As long as the contract you want to edit is still in Pending mode and has not yet been signed by all recipients, you are able to edit and send it for signatures again.
If you notice any mistakes in the contract you have just sent to the recipients, you can go to the Documents tab, under Pending status. When you find the contract in the overview, click on the three small grey dots to the right of its title and choose Edit and resend from the drop-down menu:
This will allow you to make the required changes to the content, chosen signature method, or anything else, just remember to active the Full-text editing in Create mode. Once the changes are made, you can click on Send and sign or Resend for signatures (in case you are not a signee yourself) again.
Who can edit and resend a pending contract?
If you are the creator of the document or have been granted Full access permissions by the document's owner, you can Edit and Resend it for signature while the contract is still Pending.
If you are creating the contract for external parties only, after clicking on Resend for signatures you will be able to choose if you want to keep permission of viewing the contract after it has been signed in the following pop-up window:
Here is a short video showcasing how to make changes to the signature type of a Pending contract.
Read more about monitoring the status of your contracts and how to monitor it here.