Short answer

Your Good Till Triggered (GTT) orders may be disabled, cancelled, expired, or rejected for the following reasons reasons.

Disabled

If the GTT is placed less than 0.25% from the LTP after validation.

If the shares undergo a corporate action like a bonus or a stock split.

Cancelled or Rejected

Expired

If the derivative contract has expired, the contract is no longer valid.

For equity, the GTT is valid for a year. If it fails to trigger, it expires.

You must place a fresh GTT order if your GTT has been disabled or expired.