See explanation below.
Explanation
You need to assign the Global Admin role to Irvin Sayers. You then need to configure the account to require Multi-Factor Authentication (MFA).
1. In the Microsoft 365 admin center, select Users then select Active Users.
2. Select the Irvin Sayers account to open the account properties blade.
3. In the Roles section, click on the 'Manage roles' link.
4. Select the 'Admin center access' option.
5. Select Global Administrator then click the 'Save changes' button.
The next step is to enable the account for Multi-Factor Authentication (MFA).
1. If the Irvin Sayers account is selected in the user accounts list, deselect it (click on the tick icon next to the account name). Selecting a user account changes the menu options at the top of the page; deselecting the accounts changes the menu options back.
2. Click on the 'Multi-factor authentication' link at the top of the page.
3. In the 'Multi-factor authentication' page, select the Irvin Sayers account.
4. Click the 'Enable' link on the right side of the page.
5. In the pop-up window, click the 'enable multi-factor auth' button.