In Moon Invoice, you can request a customer’s signature by sending a signature request directly from an estimate, invoice, or purchase order. When the customer clicks on the signature request link, they’ll be prompted to enter an OTP sent to their registered email or phone number for verification. Once the OTP is verified, they can provide their digital signature securely.

After the signature is completed, both you and the customer will receive a confirmation, and the document will automatically update in the respective invoice, estimate, or purchase order for your records.

Kindly refer to the link below for step-by-step guidance.

https://help.mooninvoice.com/hc/en-us/articles/12762695643161-How-to-request-signature-from-the-customers-for-the-paid-invoice