diff --git a/lib/chirp-workflow/core/src/db/pg_nats.rs b/lib/chirp-workflow/core/src/db/pg_nats.rs
index 4620bf3157..390b958e65 100644
--- a/lib/chirp-workflow/core/src/db/pg_nats.rs
+++ b/lib/chirp-workflow/core/src/db/pg_nats.rs
@@ -951,7 +951,8 @@ impl Database for DatabasePgNats {
 						SET forgotten = TRUE
 						WHERE
 							workflow_id = $1 AND
-							loop_location = $2
+							loop_location = $2 AND
+							forgotten = FALSE
 						RETURNING 1
 					),
 					forget_signal_events AS (
@@ -959,7 +960,8 @@ impl Database for DatabasePgNats {
 						SET forgotten = TRUE
 						WHERE
 							workflow_id = $1 AND
-							loop_location = $2
+							loop_location = $2 AND
+							forgotten = FALSE
 						RETURNING 1
 					),
 					forget_sub_workflow_events AS (
@@ -967,7 +969,8 @@ impl Database for DatabasePgNats {
 						SET forgotten = TRUE
 						WHERE
 							workflow_id = $1 AND
-							loop_location = $2
+							loop_location = $2 AND
+							forgotten = FALSE
 						RETURNING 1
 					),
 					forget_signal_send_events AS (
@@ -975,7 +978,8 @@ impl Database for DatabasePgNats {
 						SET forgotten = TRUE
 						WHERE
 							workflow_id = $1 AND
-							loop_location = $2
+							loop_location = $2 AND
+							forgotten = FALSE
 						RETURNING 1
 					),
 					forget_message_send_events AS (
@@ -983,7 +987,8 @@ impl Database for DatabasePgNats {
 						SET forgotten = TRUE
 						WHERE
 							workflow_id = $1 AND
-							loop_location = $2
+							loop_location = $2 AND
+							forgotten = FALSE
 						RETURNING 1
 					),	
 					forget_loop_events AS (
@@ -991,7 +996,8 @@ impl Database for DatabasePgNats {
 						SET forgotten = TRUE
 						WHERE
 							workflow_id = $1 AND
-							loop_location = $2
+							loop_location = $2 AND
+							forgotten = FALSE
 						RETURNING 1
 					)
 				SELECT 1
diff --git a/svc/pkg/workflow/db/workflow/migrations/20240809230231_fix_loop_idx.down.sql b/svc/pkg/workflow/db/workflow/migrations/20240809230231_fix_loop_idx.down.sql
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/svc/pkg/workflow/db/workflow/migrations/20240809230231_fix_loop_idx.up.sql b/svc/pkg/workflow/db/workflow/migrations/20240809230231_fix_loop_idx.up.sql
new file mode 100644
index 0000000000..ecb3949457
--- /dev/null
+++ b/svc/pkg/workflow/db/workflow/migrations/20240809230231_fix_loop_idx.up.sql
@@ -0,0 +1,30 @@
+CREATE INDEX idx_workflow_loop_events_loop_location2
+ON workflow_loop_events (workflow_id, loop_location)
+WHERE forgotten = FALSE;
+
+CREATE INDEX idx_workflow_activity_events_loop_location2
+ON workflow_activity_events (workflow_id, loop_location)
+WHERE forgotten = FALSE;
+
+CREATE INDEX idx_workflow_signal_events_loop_location2
+ON workflow_signal_events (workflow_id, loop_location)
+WHERE forgotten = FALSE;
+
+CREATE INDEX idx_workflow_sub_workflow_events_loop_location2
+ON workflow_sub_workflow_events (workflow_id, loop_location)
+WHERE forgotten = FALSE;
+
+CREATE INDEX idx_workflow_signal_send_events_loop_location2
+ON workflow_signal_send_events (workflow_id, loop_location)
+WHERE forgotten = FALSE;
+
+CREATE INDEX idx_workflow_message_send_events_loop_location2
+ON workflow_message_send_events (workflow_id, loop_location)
+WHERE forgotten = FALSE;
+
+DROP INDEX workflow_loop_events@idx_workflow_loop_events_loop_location;
+DROP INDEX workflow_activity_events@idx_workflow_activity_events_loop_location;
+DROP INDEX workflow_signal_events@idx_workflow_signal_events_loop_location;
+DROP INDEX workflow_sub_workflow_events@idx_workflow_sub_workflow_events_loop_location;
+DROP INDEX workflow_signal_send_events@idx_workflow_signal_send_events_loop_location;
+DROP INDEX workflow_message_send_events@idx_workflow_message_send_events_loop_location;