- Log in to Magento using your administrator account.
In the left sidebar, click Stores, and then under Settings, click Configuration. - Click Advanced, and then click Admin.
Under Security, in the Admin Session Lifetime (seconds) text box, - type the session timeout interval in seconds that you want to use. For example, a value of 1200 sets a timeout interval of 20 minutes.
- Click Save Config.
- Log out of Magento, and then log back in. The new session timeout interval is now active.