Hello Brice!
Unfraternally if you do not have any other account with permission to alter the conditional access that you can login to, there is nothing you personally can do. However you can contact Microsoft support and they might be able to assist :)
A quick tip for the future also is to always set up a "break the glass" account to ensure you don't end up in this situation again.
https://learn.microsoft.com/en-us/entra/identity/role-based-access-control/security-emergency-access
Last resort is just to create a new sandbox tenant if you are in a hurry and don't have much configured already in the one you got locked out of.
Hope this is helpful Best Regards, Timmy Malmgren
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