Demo/Developer: envelopes show "Sent" but signing emails are not delivered to any recipient

Environment: Demo / Developer (account-d / demo.docusign.net)
Auth: JWT (API integration)

Signing notification emails stopped being delivered to recipients around 2026-07-22.
The same account delivered emails fine on 2026-07-15 and 2026-07-17 (recipients opened
the email link and signed). Since then, no recipient receives the signing email.

What I already verified via the REST API (so this is not ordinary deliverability):
- Envelope status = "sent", recipient deliveryMethod = "email", suppressEmails is not set.
- Account flags are clean: envelopeSendingBlocked = false, suspensionStatus = "" (not suspended).
- Recipient email is correct in the recipients API (no role suffix).
- Affects BOTH an internal (account member) AND an external Gmail recipient.
- Both mailboxes checked: nothing in Inbox and nothing in Junk/Spam.
- The signing UI now shows: "This document is currently flagged as spam ... Not Spam ... Report Abuse".

This looks like the demo fraud/spam hold that withholds notification emails while the envelope
still reports status = sent. Could you please review and re-flag the account as safe?

I can share the account email, Account ID, Account name and a sample Envelope ID via private
message. Thank you.