Each of these is a refusal this regime lets a counterparty attempt, paired with the answer to it. Reading them before you write is worth more than any amount of polish on the letter itself.
It was an operational reason
high likelihoodThe airline says the flight was cancelled or you were offloaded for "operational reasons" and declines to say more.
What answers it
"Operational reasons" is not a category in the CAR. Paragraphs 1.4 and 1.5 list what excuses an airline, and every item on the list is an external event. An airline that will not identify which limb it relies on has not discharged the burden of showing the event was beyond its control. Ask for the cause in writing, in one sentence, and quote paragraph 1.4 back at it.
DGCA CAR Section 3, Series M, Part IV, Paras 1.4 and 1.5 — Paras 1.4 and 1.5
Here is a travel voucher
high likelihoodThe airline offers a voucher, often worth more than the cash entitlement, and presents it as the settlement.
What answers it
Paragraph 3.7.1 permits vouchers only with the signed agreement of the passenger. Without your signature the entitlement is cash or bank transfer. Vouchers expire, exclude peak dates and cannot be transferred; the cash cannot.
DGCA CAR Section 3, Series M, Part IV, Para 3.7.1 — Para 3.7.1
We refunded your ticket, so nothing more is owed
high likelihoodThe airline treats the refund of the fare as discharging the compensation obligation.
What answers it
Paragraph 3.3.2 requires compensation "in addition to the full refund of air ticket". The refund returns your money; the compensation is a separate statutory payment. Both are due.
DGCA CAR Section 3, Series M, Part IV, Para 3.3.2 — Para 3.3.2
Delay does not pay — but check what does
high likelihoodFor a pure delay the airline correctly says the CAR provides no compensation, and treats that as the end of the matter.
What answers it
It is the end of the CAR compensation claim, not of the matter. Paragraph 3.4.2 gives a domestic passenger delayed more than six hours the choice of an alternate flight within six hours or a full refund; paragraph 3.4.3 requires a hotel where the delay exceeds 24 hours, or six hours for a flight scheduled to depart between 2000 and 0300. On international carriage, Art. 19 of the Montreal Convention gives a claim for the loss the delay actually caused. And a delay long enough to amount to non-performance can be pursued as deficiency of service before a consumer commission.
DGCA CAR Section 3, Series M, Part IV, Para 3.4.2 — Para 3.4.2
We could not reach you
medium likelihoodRelying on paragraph 3.3.3, the airline says no compensation is payable because adequate contact information — an email address or a phone number — was not provided at booking.
What answers it
This is a real carve-out and it is the one most often correctly invoked. But it bites only where the contact details were genuinely absent. If you booked directly, or gave details to a travel agent, produce the booking confirmation showing them. Paragraph 3.3.3 also obliges airlines to require agents to pass those details on, so an agent's failure is not automatically yours.
DGCA CAR Section 3, Series M, Part IV, Para 3.3.3 — Para 3.3.3