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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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This error can occur when if the org admins do not have ops access. To troubleshoot this error, go into the org settings and select teams. Ensure that the org admin team has the ops phase toggled on.
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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.
Related Articles:
How to find if an org is set up with a sales signer
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