It seems like the ignition tumbler is going bad.
The term 'ignition tumbler' could actually mean many things. Are you having an issue turning the key? If so you may require an ignition key replacement. Security improvements in newer vehicles require a lot of work to install this item. You may require programming or special tools to fix the issue I assume you are talking about. A qualified technician, such as one from YourMechanic can assist you in diagnosis and repair.
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