diff --git a/plugins/op_waf/waf/lua/init.lua b/plugins/op_waf/waf/lua/init.lua
index 33ded01ad..4a6792e1f 100644
--- a/plugins/op_waf/waf/lua/init.lua
+++ b/plugins/op_waf/waf/lua/init.lua
@@ -346,7 +346,7 @@ local function waf_cc_increase()
     if params['uri_request_args']['token'] then
         local args_token = params['uri_request_args']['token']
         if args_token == make_token then
-            ngx.shared.waf_limit:set(cache_token, 1, config['safe_verify']['time'])
+            ngx.shared.waf_limit:set(cache_token, 1, tonumber(config['safe_verify']['time']))
             local data = get_return_state(0, "ok")
             ngx.say(json.encode(data))
             ngx.exit(200)