The problematic Netgear R6400 router cannot be connected after uploading the new firmware v. 1.0.1.7

After uploading the new firmware v. 1.0.1.72, the router will not connect to the back pages via several Internet browsers, even if they are updated.

It always writes it, it can't be used. Only always after the second attempt.

When I return the old firmware v. 1.0.1.68, everything is fine and the router works as it should.

Please, give me an advice.

Thank you.

Model: R6400 | AC1750 Intelligent WiFi router