You should post the Year and Model of your Car. I think in on some of the Later Models you need to stick 2 wires into the tumbler to remove it.

I and several others I this last 1.5 Years have had something inside of the Steering Colum Lock break. The Steering Colum Lock is between the Tumbler and the Ignition Switch.
In My Case that Tube that turns the Ignition Switch cracked off.

When I took everything apart I also found that while the Ignition Switch part worked one of the Contacts was burnt badly.

Most places sell the Steering Colum Lock as an assembly. It comes with the Colum Lock, the Ignition Switch and the Vacuum Shutoff Valve that attaches to the Ignition Switch.

I bought a new one from the Mercedes Dealer and it was about $140. It was made by Neiman in France.
Some Sellers sell the Neiman/Valeo made in France assembly for about $20 less than I paid.
If you see an Ad for less than that read it closely be sure it is an assembly and not just the bare Steering Colum Lock.

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84 300D, 82 Volvo 244Gl Diesel