Sending, receiving, and organizing email in Outlook.com
Hi, I'm John!
Have you already verified your account and updated your security information recently?
Sometimes sending limits can stay low if the system detects unusual activity or if the account hasn’t been fully verified.
If you haven't already, the best place to start is making sure your account is fully verified, check that your security info (like your phone number or alternate email) is up to date at https://account.microsoft.com Once that’s done, the limits often lift within 24 hours.
For more detailed guidance please see "How can I increase sending limits?" section here: https://support.microsoft.com/office/sending-limits-in-outlook-com-279ee200-594c-40f0-9ec8-bb6af7735c2e