diff --git a/app/Filters/InvoiceFilters.php b/app/Filters/InvoiceFilters.php
index c155d2061516..f599511ee13d 100644
--- a/app/Filters/InvoiceFilters.php
+++ b/app/Filters/InvoiceFilters.php
@@ -185,7 +185,7 @@ class InvoiceFilters extends QueryFilters
      * @param string sort formatted as column|asc
      * @return Builder
      */
-    public function sort(string $sort) : Builder
+    public function sort(string $sort = '') : Builder
     {
         $sort_col = explode('|', $sort);