Hi @OZesatiSA ,
You'll need to transition the service account to an Owner role.
As a safety measure, I would suggest adding an extra Owner role. The Owner role has the same access as the Service Administrator.
To remove the Service Administrator, you need to have a user who is assigned the Owner role at subscription scope without conditions to avoid orphaning the subscription. A subscription Owner has the same access as the Service Administrator. You can remove the Service Administrator role under Access control (IAM) > Classic aministrators
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