oauth is not working

[timofey1]

One of our users experience a problem passing oauth flow.

• User is redirected to authorize.net from the service provider: https://account.authorize.net/oauth/authorize?sub=oauth&client_id=i6Fmq0B9qv&scope=read,write&state=...
• Redirected to: https://account.authorize.net/ui/themes/anet/logon.aspx?sub=oauth&client_id=i6Fmq0B9qv&scope=read,wr...
• Redirected to: https://login.authorize.net?cobrand=anet&sub=oauth&client_id=i6Fmq0B9qv&scope=read%2cwrite&state=05c...
• Login form is opened. (Should be special form for connecting account, as sad in documentation https://developer.authorize.net/api/reference/features/oauth.html)
• After entering credentials redirected to: /ui/themes/anet/oauth/grantauthorization.aspx?sub=oauth&redirect_uri=https%3a%2f%2fapp.pandadoc.com%2fintegrations%2fgetpaid%2fconnect%2fauthorize_net%2f&client_id=i6Fmq0B9qv&scope=read%2cwrite&state=05c20e7e-b0a4-45fb-92b7-fa28e7e9526a&oauthchecked=true&client_name=Prod%20application
• Redirected to: /ui/themes/anet/Logon.aspx?redirect_uri=https%3a%2f%2fapp.pandadoc.com%2fintegrations%2fgetpaid%2fconnect%2fauthorize_net%2f&client_id=i6Fmq0B9qv&scope=read%2cwrite&state=05c20e7e-b0a4-45fb-92b7-fa28e7e9526a
• Redirected to: https://login.authorize.net?cobrand=anet&redirect_uri=https%3a%2f%2fapp.pandadoc.com%2fintegrations%...
• Login form is opened.
• After entering credentials, authorize.net home page is opened.

Our client uses chrome browser. I tried chrome and safari browsers. Reproduced that in both

[timofey1]

Also tried firefox. - the same