This article provides an explanation and fix for the Adobe Commerce 2.3.X issue where the checkout gets stuck if Authorize.net is used, with the ‘Cannot read property ‘length’ of null’ error message in the browser console log.
The core Adobe Commerce Authorize.Net payment integration is deprecated since 2.3.4 and will be completely removed in 2.4.0. Use the official extension from marketplace instead.
Steps to reproduce
The Authorize.net iframe is loaded.
Ajax spinner is displayed, and the page never loads. The following JS error is displayed in the browser console log: ‘Uncaught TypeError: Cannot read property ‘length’ of null at b (jstest.authorize.net/v1/AcceptCore.js:1)’
One of the most common reasons for this issue is the Public Client Key not being specified in the Authorize.Net configuration in the Commerce Admin.
Under Stores > Settings > Configuration > Sales > Payment Methods, in the Authorize.net section, check if the value is specified in the Public Client Key field. If it is empty, enter the key value from your Authorize.Net merchant account.
For the changes to be applied, clean the cache by running