diff --git a/src/nassella.scm b/src/nassella.scm
index 8c77a1b..75c94df 100644
--- a/src/nassella.scm
+++ b/src/nassella.scm
@@ -1046,7 +1046,7 @@ chmod -R 777 /opt/keys")))
 ;; guessed at the length
 (define (valid-nextcloud-user? v)
   (if (string? v)
-      (irregex-match? (irregex "[a-zA-Z0-9-_\\. @]{1,64}") v)
+      (irregex-match? (irregex "[a-zA-Z0-9\\-_\\. @]{1,64}") v)
       #f))
 
 ;; Seems to be few restrictions other than a default that it should