Mercedes w 211 2003 key does not turn in ignition

Mercedes w 211 2003
Key does not turn ignition eis
Unit is a friend got both
Keys tried eis with China
Ignition coil ring tester
The red light comes on
Bright for 7 seconds than
The key will not turn tried
Both keys I usually do not
Do Mercedes or BMW cars
I know the steering lock
Problems plus read the eis
Ignition can fail can any mercedes
Expert help cannot run
Diagnostic