diff --git a/web/app/components/workflow/header/checklist.tsx b/web/app/components/workflow/header/checklist.tsx
index 374726cbeb..c14ab1f6e5 100644
--- a/web/app/components/workflow/header/checklist.tsx
+++ b/web/app/components/workflow/header/checklist.tsx
@@ -142,8 +142,8 @@ const WorkflowChecklist = ({
                             }
                             {
                               node.varErrorMessage?.map((errorMessage: string) => (
-                                <div className='rounded-b-lg bg-gray-25 px-3 py-2'>
-                                  <div className='flex text-xs leading-[18px] text-gray-500'>
+                                <div className='rounded-b-lg px-3 py-2'>
+                                  <div className='flex text-xs leading-[18px] text-text-tertiary'>
                                     <AlertTriangle className='mr-2 mt-[3px] h-3 w-3 text-[#F79009]' />
                                     {errorMessage}
                                   </div>
diff --git a/web/app/components/workflow/nodes/assigner/default.ts b/web/app/components/workflow/nodes/assigner/default.ts
index 32dac73b36..cabf18af77 100644
--- a/web/app/components/workflow/nodes/assigner/default.ts
+++ b/web/app/components/workflow/nodes/assigner/default.ts
@@ -51,11 +51,12 @@ const nodeDefault: NodeDefault<AssignerNodeType> = {
 
   checkVarValid(payload: AssignerNodeType, varMap: Record<string, Var>, t: any) {
     const errorMessageArr: string[] = []
-    const variables_warnings = getNotExistVariablesByArray(payload.items.map(item => item.variable_selector ?? []) ?? [], varMap)
+    const items = payload.items ?? []
+    const variables_warnings = getNotExistVariablesByArray(items.map(item => item.variable_selector ?? []) ?? [], varMap)
     if (variables_warnings.length)
       errorMessageArr.push(`${t('workflow.nodes.assigner.assignedVariable')} ${t('workflow.common.referenceVar')}${variables_warnings.join('、')}${t('workflow.common.noExist')}`)
 
-    const value_warnings = getNotExistVariablesByArray(payload.items.map(item => item.value ?? []) ?? [], varMap)
+    const value_warnings = getNotExistVariablesByArray(items.map(item => item.value ?? []) ?? [], varMap)
     if (value_warnings.length)
       errorMessageArr.push(`${t('workflow.nodes.assigner.setVariable')} ${t('workflow.common.referenceVar')}${value_warnings.join('、')}${t('workflow.common.noExist')}`)