1. It is recommended to enable Cookies in the browser settings:
Google Chrome - go to the page chrome://settings/cookies, section "General settings", select the item "Show all cookies"
Yandex Browser - go to the browser://settings/content page, scroll down to "Cookies", select "Allowed" and uncheck the "Block data and files of the third-party sites" item.
Microsoft Edge - go to the edge://settings/content page, select "Cookies and site data" and turn-on "Allow sites to save and read cookie data (recommended) function.
After this check if the problem is still there. If so, move to step 2.
2. Clear browser cookies
Google Chrome - chrome: // settings / siteData - "Delete everything"
Yandex Browser - browser: // settings / siteData - "Delete everything"
Microsoft Edge – edge://settings/siteData – "Remove all"
After this check if the problem is still there. If so, move to step 3.
3. Use the Incognito mode in the browser (Ctrl + Shift + N) and pass the exam in it. In Google Chrome, when you switch to Incognito, make sure that the "Third-party cookies block" item is disabled, as in the screenshot:
If the problem persists, move to step 4.
4. Use another browser – you have checked in Google Chrome, then try using Yandex browser or Microsoft Edge; if you originally used Yandex browser, try checking in Google Chrome or Microsoft Edge.
Important: only one browser should be running, all others should be closed. Yandex browser must also be closed in the system tray by right-clicking on its icon "close the browser". If the problem persists in another browser, follow steps 1,2,3 in it.