diff --git a/templates/override.conf.erb b/templates/override.conf.erb
index 0766512..3d13498 100644
--- a/templates/override.conf.erb
+++ b/templates/override.conf.erb
@@ -9,7 +9,7 @@ ExecStart=/usr/bin/prometheus \
   --storage.tsdb.path=/var/lib/prometheus \
   --storage.tsdb.retention.time=<%= @ps_retention_time %> \
   --storage.tsdb.retention.size=<%= @ps_retention_size %> \
-  --storage.tsdb.wal-segment-size=<%= @psps_wal_seg_size %> \
+  --storage.tsdb.wal-segment-size=<%= @ps_wal_seg_size %> \
   --web.enable-remote-write-receiver \
   --web.enable-lifecycle \
   --storage.tsdb.wal-compression
\ No newline at end of file