diff --git a/config/bundle_focal.yaml b/config/bundle_focal.yaml
index 6f30f8e..8da07c0 100644
--- a/config/bundle_focal.yaml
+++ b/config/bundle_focal.yaml
@@ -1076,7 +1076,6 @@ applications:
       #url: https://landscape.example.com/message-system
   prometheus:
     charm: cs:prometheus2
-    series: bionic
     bindings:
       "": *oam-space
     num_units: 1
@@ -1222,7 +1221,6 @@ applications:
 #        -----END PGP PUBLIC KEY BLOCK-----
   prometheus-ceph-exporter:
     charm: cs:prometheus-ceph-exporter
-    series: bionic
     bindings:
       "": *oam-space
       ceph: *ceph-public-space