diff --git a/llamabot.js b/llamabot.js
index cf6ad65..7e159e8 100644
--- a/llamabot.js
+++ b/llamabot.js
@@ -197,7 +197,7 @@ async function generateResponse(conversation, message) {
     let time = 0
     // define a function that shows the system load percentage and updates the message
     const showSystemLoad = async () => {
-        time = time + process.env.REFRESH_INTERVAL;
+        time = Number(time) + Number(process.env.REFRESH_INTERVAL);
         cpuStat.usagePercent(function(err, percent, seconds) {
           if (err) {
             return console.log(err);