Hi @Iurii Salagaev ,
As per my test, I am getting recordAutomatically property as true in the response and when I am joining the meeting using joinWebURL it started recording automatically. Could you please verify the same from your end by join in to the meeting?
Please try application-post-onlinemeetings Graph API V1.0 and if you are still facing the issue with V1.0 also , I would recommend you to raise a support case with Microsoft Graph, a Support Engineer will be able to assist you better.You can raise support ticket from http://aad.portal.azure.com/ or https://admin.microsoft.com/#/support/requests.
Hope this helps.
If the answer is helpful, please click Accept Answer and kindly upvote it. If you have any further questions about this answer, please click Comment.