# Server to Server Oauth **URL:** \ **Category:** Meetings\ **Tags:** server-to-server, token-tolerance, s2s-oauth\ **Created:** [February 10, 2023, 1:24pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901 "2023-02-10T13:24:24Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![EVant](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/evant/32/3511_2.png) [@EVant](https://devforum.zoom.us/u/EVant)\ **Post date:** [February 10, 2023, 1:24pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/1 "2023-02-10T13:24:24Z")
Hello I have developed an app which is accessing meeting status within a loop. most of the time it works but sometimes I receive an error. `401 "Invalid access token."` The process last a few minutes so I don’t reach the hour limit Why is it occurring ? How can I check the validity of a recently generated token or avoid the problem ? Thanks ---
**Author:** ![elisa.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/elisa.zoom/32/47836_2.png) [@elisa.zoom](https://devforum.zoom.us/u/elisa.zoom)\ **Post date:** [February 14, 2023, 2:53pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/2 "2023-02-14T14:53:27Z")
Hi @EVant The access\_token generated with the Server to Server Oauth app has an expiration time of 1 hour and once you generate a new token, the previous one gets invalidated. It seems strange to me that you are getting this error if you are creating new tokens within minutes ---
**Author:** ![EVant](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/evant/32/3511_2.png) [@EVant](https://devforum.zoom.us/u/EVant)\ **Post date:** [February 14, 2023, 3:15pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/3 "2023-02-14T15:15:03Z")
This happened 3 times. Each times and within a few minutes after the token generation and after several api calls ---
**Author:** ![elisa.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/elisa.zoom/32/47836_2.png) [@elisa.zoom](https://devforum.zoom.us/u/elisa.zoom)\ **Post date:** [February 16, 2023, 9:18pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/4 "2023-02-16T21:18:30Z")
@EVant Interesting. Do you happen to have the API calls you made (endpoints) and the date and time when this issue happened? ---
**Author:** ![EVant](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/evant/32/3511_2.png) [@EVant](https://devforum.zoom.us/u/EVant)\ **Post date:** [February 17, 2023, 7:09am UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/5 "2023-02-17T07:09:40Z")
Although the problem usually occurs in loop processing, this time there was only one call. `2023-02-16 13:00:02,913 /meetings/89525337799/status` In this case, I generated the token, called the API, and received a 401 error message that was caught. I immediately requested another token and it worked ---
**Author:** ![EVant](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/evant/32/3511_2.png) [@EVant](https://devforum.zoom.us/u/EVant)\ **Post date:** [February 17, 2023, 2:10pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/6 "2023-02-17T14:10:05Z")
here is an other example. end point: [https://api.zoom.us/v2/users/\*user\*/meetings](https://api.zoom.us/v2/users/*user*/meetings) In a loop Start at` 2023-02-17 14:49:24,256` 97 success API calls `2023-02-17 14:50:02,006 **ERROR** ` update header 300 success API calls `2023-02-17 14:54:01,941 **ERROR** ` update header 305 success API calls ---
**Author:** ![elisa.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/elisa.zoom/32/47836_2.png) [@elisa.zoom](https://devforum.zoom.us/u/elisa.zoom)\ **Post date:** [February 23, 2023, 7:47pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/7 "2023-02-23T19:47:16Z")
Hi @EVant I am really sorry for the late reply I will send you a private message to follow up ---
**Author:** ![gianni.zoom](https://sea2.discourse-cdn.com/flex016/user_avatar/devforum.zoom.us/gianni.zoom/32/32523_2.png) [@gianni.zoom](https://devforum.zoom.us/u/gianni.zoom)\ **Post date:** [March 15, 2023, 6:12pm UTC](https://devforum.zoom.us/t/server-to-server-oauth/82901/8 "2023-03-15T18:12:42Z")
This behavior is similar to another developer. Linking the ticket here for reference: > [@Issue migrating JWT to Server-to-Server OAuth](https://devforum.zoom.us/t/issue-migrating-jwt-to-server-to-server-oauth/82340/8): > > This is currently under escalation review. Sharing the ticket number here for other developer and Developer Advocates who may encounter someone experiencing the same behavior (ZSEE-85355).