diff --git a/scripts/fluidd.sh b/scripts/fluidd.sh
index c59339c..bff2219 100644
--- a/scripts/fluidd.sh
+++ b/scripts/fluidd.sh
@@ -377,11 +377,11 @@ function patch_fluidd_update_manager(){
   local moonraker_configs
   moonraker_configs=$(find "$(get_klipper_cfg_dir)" -type f -name "moonraker.conf")
   for conf in ${moonraker_configs}; do
-    status_msg "Adding Fluidd to update manager in file:\n       ${conf}"
-    ### add new line to conf if it doesn't end with one
-    [[ $(tail -c1 "${conf}" | wc -l) -eq 0 ]] && echo "" >> "${conf}"
-    ### add Fluidds update manager section to moonraker.conf
-    if grep -Eq "[update_manager fluidd]" "${conf}"; then
+    if ! grep -Eq "[update_manager fluidd]" "${conf}"; then
+      ### add new line to conf if it doesn't end with one
+      [[ $(tail -c1 "${conf}" | wc -l) -eq 0 ]] && echo "" >> "${conf}"
+      ### add Fluidds update manager section to moonraker.conf
+      status_msg "Adding Fluidd to update manager in file:\n       ${conf}"
       /bin/sh -c "cat >> ${conf}" << MOONRAKER_CONF
 
 [update_manager fluidd]
diff --git a/scripts/klipperscreen.sh b/scripts/klipperscreen.sh
index 50209bd..451efe9 100644
--- a/scripts/klipperscreen.sh
+++ b/scripts/klipperscreen.sh
@@ -189,11 +189,11 @@ function patch_klipperscreen_update_manager(){
   local moonraker_configs
   moonraker_configs=$(find "$(get_klipper_cfg_dir)" -type f -name "moonraker.conf")
   for conf in ${moonraker_configs}; do
-    status_msg "Adding KlipperScreen to update manager in file:\n       ${conf}"
-    ### add new line to conf if it doesn't end with one
-    [[ $(tail -c1 "${conf}" | wc -l) -eq 0 ]] && echo "" >> "${conf}"
-    ### add KlipperScreens update manager section to moonraker.conf
-    if grep -Eq "[update_manager KlipperScreen]" "${conf}"; then
+    if ! grep -Eq "[update_manager KlipperScreen]" "${conf}"; then
+      ### add new line to conf if it doesn't end with one
+      [[ $(tail -c1 "${conf}" | wc -l) -eq 0 ]] && echo "" >> "${conf}"
+      ### add KlipperScreens update manager section to moonraker.conf
+      status_msg "Adding KlipperScreen to update manager in file:\n       ${conf}"
       /bin/sh -c "cat >> ${conf}" << MOONRAKER_CONF
 
 [update_manager KlipperScreen]
diff --git a/scripts/mainsail.sh b/scripts/mainsail.sh
index c441651..323311b 100644
--- a/scripts/mainsail.sh
+++ b/scripts/mainsail.sh
@@ -499,11 +499,11 @@ function patch_mainsail_update_manager(){
   local moonraker_configs
   moonraker_configs=$(find "$(get_klipper_cfg_dir)" -type f -name "moonraker.conf")
   for conf in ${moonraker_configs}; do
-    status_msg "Adding Mainsail to update manager in file:\n       ${conf}"
-    ### add new line to conf if it doesn't end with one
-    [[ $(tail -c1 "${conf}" | wc -l) -eq 0 ]] && echo "" >> "${conf}"
-    ### add Mainsails update manager section to moonraker.conf
-    if grep -Eq "[update_manager mainsail]" "${conf}"; then
+    if ! grep -Eq "[update_manager mainsail]" "${conf}"; then
+      ### add new line to conf if it doesn't end with one
+      [[ $(tail -c1 "${conf}" | wc -l) -eq 0 ]] && echo "" >> "${conf}"
+      ### add Mainsails update manager section to moonraker.conf
+      status_msg "Adding Mainsail to update manager in file:\n       ${conf}"
       /bin/sh -c "cat >> ${conf}" << MOONRAKER_CONF
 
 [update_manager mainsail]