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This error can occur when the homeowner’s name entered in the credit Qualification phase does not match the name entered in the Contact phase. If the contract is already signed, the customer has to cancel the workflow and generate a new quote and contract based on the updated legal contact spelling. See article: How to update homeowner contact information in Qualification for a new or revised contract
Error DOC-029: Could not find a valid Contract Signer
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In one case, the authorized signers for the particular organization did not have operations access, therefore their contract was blocked with this error message. In the org settings under teams - org admin, ensure that the operations phase is toggled on.
Error QUAL - 026 An Error Occurred: This error means that an invalid email address was used. They should ensure the email address is unique to the applicant and not used elsewhere in our platform.
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Related Articles:
How to find if an org is set up with a sales signer
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How to update homeowner contact information for a new or revised contract