# Failed to receive a message: UNIQUE constraint failed: contacts.id: Error code 1555: A PRIMARY KEY constraint failed

**URL:** <https://forum.delta.chat/t/failed-to-receive-a-message-unique-constraint-failed-contacts-id-error-code-1555-a-primary-key-constraint-failed/4416>\
**Category:** User Testing\
**Tags:** android\
**Created:** [December 6, 2025, 11:31pm UTC](https://forum.delta.chat/t/failed-to-receive-a-message-unique-constraint-failed-contacts-id-error-code-1555-a-primary-key-constraint-failed/4416 "2025-12-06T23:31:42Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![rako](https://forum.delta.chat/letter_avatar_proxy/v4/letter/r/e79b87/32.png) [@rako](https://forum.delta.chat/u/rako)\
**Post date:** [December 6, 2025, 11:31pm UTC](https://forum.delta.chat/t/failed-to-receive-a-message-unique-constraint-failed-contacts-id-error-code-1555-a-primary-key-constraint-failed/4416/1 "2025-12-06T23:31:42Z")

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I’m hitting this message with deltachat 2.25.0. It’s a non-chatmail relay:

❌ Failed to receive a message: UNIQUE constraint failed: contacts.id: Error code 1555: A PRIMARY KEY constraint failed. Please report this bug to delta@merlinux.eu or [https://support.delta.chat/](https://support.delta.chat/).

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**Author:** ![link2xt](https://forum.delta.chat/user_avatar/forum.delta.chat/link2xt/32/1971_2.png) [@link2xt](https://forum.delta.chat/u/link2xt)\
**Post date:** [December 7, 2025, 6:19pm UTC](https://forum.delta.chat/t/failed-to-receive-a-message-unique-constraint-failed-contacts-id-error-code-1555-a-primary-key-constraint-failed/4416/2 "2025-12-07T18:19:18Z")

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It is the same issue as [SQLITE\_CONSTRAINT\_PRIMARYKEY when receiving a message with core 2.25.0 · Issue #7554 · chatmail/core · GitHub](https://github.com/chatmail/core/issues/7554), should be fixed in the next release.

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**Author:** ![rako](https://forum.delta.chat/letter_avatar_proxy/v4/letter/r/e79b87/32.png) [@rako](https://forum.delta.chat/u/rako)\
**Post date:** [December 7, 2025, 6:40pm UTC](https://forum.delta.chat/t/failed-to-receive-a-message-unique-constraint-failed-contacts-id-error-code-1555-a-primary-key-constraint-failed/4416/3 "2025-12-07T18:40:32Z")

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Damn, should have checked, thanks !

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**Author:** ![r10s](https://forum.delta.chat/user_avatar/forum.delta.chat/r10s/32/1513_2.png) [@r10s](https://forum.delta.chat/u/r10s)\
**Post date:** [October 6, 2026, 3:29pm UTC](https://forum.delta.chat/t/failed-to-receive-a-message-unique-constraint-failed-contacts-id-error-code-1555-a-primary-key-constraint-failed/4416/4 "2026-10-06T15:29:03Z")

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