How to fix blocklist bounces

You got Bounce diagnostics mention blocked-list or spam concentration. Lumail classified enough permanent bounces (at least 10, and ≥ 2% of sent in the window) with blocked-list / spam-style diagnostic codes.

This is not a full public-blocklist monitor. It only uses bounce text Lumail already received.

What to change

Treat it as a reputation or list problem, not a missing DNS row (unless you also have domain auth alerts).

1. Open Settings → Deliverability and read the bounce diagnostics.
2. Stop sending to the same unengaged list.
3. Remove the bouncing addresses — they are already suppressed; do not re-import.
4. If a specific destination (e.g. one consumer ISP) dominates, pause that segment and fix list quality before retrying.
5. Confirm SPF, DKIM, and DMARC are passing — domain guides.
6. If you recently moved from another ESP, expect leftover blocklist / filter memory. Warm up with engaged recipients only.

If the copy mentions a public list (Spamhaus, etc.), request delisting only after the list is clean and auth passes. Relisting is immediate if you keep sending the same traffic.

After it recovers

The alert resolves when blocked-list bounce volume drops below the threshold (under 10 events or under 2% of sent on an adequate sample).

Related

• How to lower bounce rate
• How to lower complaint rate
• Sender Health