Hey there, MURLIE n
Your tenant is marked as inactive when no one has signed into your tenant for more then two-hundred days. Once this time has passed, the system marks your tenant as inactive. You then have twenty days to reach out to support to re-activate your tenant.
If you are within the twenty-day window, please reach out to support by using the contact numbers here: https://support.microsoft.com/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2
Please select the phone number in your region to speak to support.
If it has been longer then 220 days, please be aware that everything has been deleted and support are unable to retrieve your tenant. Thus, you would need to create a new tenant, unfortunately.
I hope this information helps,
Nathan