Hero Motocorp — Maestro edge key lock problem

Myself having maestro edge (reg no- RJ30SQ8076) purchased on Aug' 17, from last 1.5 years I had a problem on key lock, whenever I insert key a key sign appeared on display and it does not allow for ignition, I visited nearby service centre & as adviced key lock has been replaced by new one on[protected] as per invoice).
But now last 7 days the same problem happened.
I fed-up with this problem happened twice within a year.
I never seen/happened about this problem.
Please look into this and solve as early as possible.
Key set change invoice is attached please find.