Hi @Liz Colvin
When an account gets compromised, hackers sometimes change mail rules, forwarding settings, or even block incoming emails. Since you have already checked everything and secured the account, your next step should be to complete the formal account reinstatement form: https://www.microsoft.com/digitalsafety/account-reinstatement
Just to be safe, I’d recommend to sign out everywhere. Visit: https://account.live.com/proofs/manage/additional Scroll down to Sign me out and select "Sign me out".
- After signing out everywhere, please monitor if the issue persists in the coming hours.