You're all probably tired of me bringing this up once again, but this is a friendly reminder that today is the day where Mojang Accounts are being retired and Microsoft Accounts will be required to log in.
While not all Mojang Accounts will stop working some may find that they can no longer log into Minecraft until they migrate their account. For those that are still able to log in with your Mojang Account use this time to migrate over to the new login system so you do not experience any interrupted play.
If you have any questions please review Mojang Studio's FAQ for Account Migration here.