Hi Vincent,
Thank you for contacting us, and I'm sorry to hear about your situation. In order to reset your password you will need to reset your mSecure account. After the account is reset, you will be able to set a new password, then you can reinstall mSecure on your devices and sign back in to the account.
It look like you already know this, but I did want to confirm that all of the data currently stored in the account will be lost. There is no way to reset the password for an account without destroying the data currently stored in the app.
Here is a link to our support article for resetting your mSecure account: Account Reset
Vincent