As an Internet user: delete cookies and reset the browser. The HTTP 400 error occurs if the HTTP header is too long. In principle, headers don’t have a size limit, however, the target server may have set a limit. The header consists of several fields, in which requests and answers are defined.
For More Information Please Refer: https://www.ionos.com/digitalguide/hosting/technical-matters/http-400-bad-request-finding-the-causes/