diff --git a/packages/builder/src/helpers/duplicate.ts b/packages/builder/src/helpers/duplicate.ts
index 4816bcfd7b..35beb4df38 100644
--- a/packages/builder/src/helpers/duplicate.ts
+++ b/packages/builder/src/helpers/duplicate.ts
@@ -70,10 +70,16 @@ export const duplicateName = (name: string, allNames: string[]) => {
  * @param getName optional function to extract the name for an item, if not a
  *  flat array of strings
  */
-export const getSequentialName = (
-  items: string[],
+export const getSequentialName = <T extends string | object>(
+  items: T[],
   prefix: string,
-  { getName = (x: string) => x, numberFirstItem = false } = {}
+  {
+    getName,
+    numberFirstItem,
+  }: {
+    getName: (item: T) => string
+    numberFirstItem?: boolean
+  }
 ) => {
   if (!prefix?.length || !getName) {
     return null
diff --git a/packages/builder/src/stores/builder/rowActions.ts b/packages/builder/src/stores/builder/rowActions.ts
index 9576eccd1b..2b3077926e 100644
--- a/packages/builder/src/stores/builder/rowActions.ts
+++ b/packages/builder/src/stores/builder/rowActions.ts
@@ -62,7 +62,7 @@ export class RowActionStore extends BudiStore<RowActionState> {
       const existingRowActions = get(this)[tableId] || []
       name = getSequentialName(existingRowActions, "New row action ", {
         getName: x => x.name,
-      })
+      })!
     }
 
     if (!name) {