diff --git a/CHANGELOG.md b/CHANGELOG.md
index ff42cb86a..742bc28db 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 # Changelog Fab-manager
 
+- Fix a bug: wrong reservations count for spaces in availabilities export (#415)
+
 ## v5.5.7 2022 December 13
 
 - Fix a bug: unable to update/delete a space
diff --git a/app/views/exports/availabilities_index.xlsx.axlsx b/app/views/exports/availabilities_index.xlsx.axlsx
index c08414983..58748e4c4 100644
--- a/app/views/exports/availabilities_index.xlsx.axlsx
+++ b/app/views/exports/availabilities_index.xlsx.axlsx
@@ -88,7 +88,7 @@ if Setting.get('spaces_module')
       ((a.end_at - a.start_at) / slot_duration.minutes).to_i.times do |i|
         start_at = a.start_at + (i * slot_duration).minutes
         end_at = a.start_at + (i * slot_duration).minutes + slot_duration.minutes
-        reservations = a.slots.where(start_at: start_at).count
+        reservations = a.slots_reservations.where(slots: { start_at: start_at }).count
 
         data = [
           start_at.to_date,