I'm trying to validate a signature for a pdf file.
When I open the document a banner "At least one signature is invalid" with a signature panel button appears. (Refer to figure 1.)
When I open the signature panel and right click on the signature "Rev.1: Signed by Preflight Ticket Signature" and click "validate signature"
the error message appears (figure 2)
When I click "ok" another error message appears (figure 3).
How do I fix this problem?
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