diff --git a/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/down.sql b/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/down.sql
index 0c0ad782..6fbb8848 100644
--- a/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/down.sql
+++ b/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/down.sql
@@ -1,7 +1,7 @@
 alter table multicast_group
   alter column class_b_ping_slot_nb_k type integer;
 
-update multicast_group set class_b_ping_slot_nb_k = pow(2, class_b_ping_slot_nb_k) * 32;
+update multicast_group set class_b_ping_slot_nb_k = coalesce(pow(2, nullif(class_b_ping_slot_nb_k, 0)) * 32, 0);
 
 alter table multicast_group
   rename column class_b_ping_slot_nb_k to class_b_ping_slot_period;
diff --git a/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/up.sql b/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/up.sql
index f280ef1f..969de6e3 100644
--- a/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/up.sql
+++ b/chirpstack/migrations/2024-03-26-134652_align_multicast_ping_slot_config/up.sql
@@ -1,7 +1,7 @@
 alter table multicast_group
   rename column class_b_ping_slot_period to class_b_ping_slot_nb_k;
 
-update multicast_group set class_b_ping_slot_nb_k = log(2, class_b_ping_slot_nb_k / 32);
+update multicast_group set class_b_ping_slot_nb_k = coalesce(log(2, nullif(class_b_ping_slot_nb_k, 0) / 32), 0);
 
 alter table multicast_group
   alter column class_b_ping_slot_nb_k type smallint;