diff --git a/README.md b/README.md
index e4f2a66..b2dada1 100644
--- a/README.md
+++ b/README.md
@@ -317,11 +317,15 @@ If the job passes the frontend check but the backend never becomes healthy:
 
 1. Open the failed job log and read **Backend logs** (printed before rollback).
 2. Match the error to a fix — do not guess:
+   - **`Detected applied migration not resolved locally: 6`** (or 2, 4) — prod DB still lists
+     dev seed migrations removed from `db/migration`. Fixed in app via `ProdFlywayConfig`
+     (repair before migrate); redeploy after that commit is on `master`.
    - **`password authentication failed`** — DB credentials in the running stack do not match
      what Postgres was initialized with; fix credentials or Postgres password to match (only
      wipe the volume if you accept losing prod data).
    - **`Production requires ADMIN_EMAIL and ADMIN_PASSWORD`** — add those Forgejo secrets.
-   - **Flyway / migration errors** — fix schema or migration history before redeploying.
+   - **Other Flyway / migration errors** — read the stack trace; do not wipe the volume unless
+     the log clearly requires it.
 3. **DBeaver from your laptop** — prod Postgres binds to `127.0.0.1:5433` on the server only.
    Use an SSH tunnel, then host `localhost` port `5433` (not `192.168.0.59` directly).
 
diff --git a/backend/src/main/java/se/bilhalsning/config/ProdFlywayConfig.java b/backend/src/main/java/se/bilhalsning/config/ProdFlywayConfig.java
new file mode 100644
index 0000000..bdf38b6
--- /dev/null
+++ b/backend/src/main/java/se/bilhalsning/config/ProdFlywayConfig.java
@@ -0,0 +1,24 @@
+package se.bilhalsning.config;
+
+import org.flywaydb.core.Flyway;
+import org.springframework.boot.flyway.autoconfigure.FlywayMigrationStrategy;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Profile;
+
+@Configuration
+@Profile("prod")
+public class ProdFlywayConfig {
+
+    /**
+     * Prod databases may record dev seed migrations (V2, V4, V6) from before they moved to
+     * db/dev-migration/. Repair marks those missing scripts as deleted so validate passes.
+     */
+    @Bean
+    public FlywayMigrationStrategy prodFlywayMigrationStrategy() {
+        return (Flyway flyway) -> {
+            flyway.repair();
+            flyway.migrate();
+        };
+    }
+}
diff --git a/backend/src/test/java/se/bilhalsning/config/ProdFlywayConfigTest.java b/backend/src/test/java/se/bilhalsning/config/ProdFlywayConfigTest.java
new file mode 100644
index 0000000..e7909b1
--- /dev/null
+++ b/backend/src/test/java/se/bilhalsning/config/ProdFlywayConfigTest.java
@@ -0,0 +1,33 @@
+package se.bilhalsning.config;
+
+import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.mock;
+
+import org.flywaydb.core.Flyway;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.flyway.autoconfigure.FlywayMigrationStrategy;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.ActiveProfiles;
+import org.mockito.InOrder;
+
+@SpringBootTest(
+        properties = {
+            "app.admin.email=admin@test.se",
+            "app.admin.password=test-password",
+        })
+@ActiveProfiles("prod")
+class ProdFlywayConfigTest {
+
+    @Autowired
+    private FlywayMigrationStrategy flywayMigrationStrategy;
+
+    @Test
+    void shouldRepairBeforeMigrateOnProd() {
+        Flyway flyway = mock(Flyway.class);
+        flywayMigrationStrategy.migrate(flyway);
+        InOrder order = inOrder(flyway);
+        order.verify(flyway).repair();
+        order.verify(flyway).migrate();
+    }
+}