Upvote:1
At this point I'd personally just give up. Your losses of 80 pounds would not be worth a lawsuit and at this point this is your only option.
Upvote:2
I understood others airlines compensate/fix if they damage a baby buggy.
Most other airlines in the world offering carriage on an international ticket would be bound by the MontrΓ©al Convention, which would make them strictly liable for damage caused to checked baggage while it is in their care. The Convention also makes it very easy to bring claims against a foreign carrier in your home country, either as the passenger or as the passenger's insurer (through subrogation). In the UK you can actually bring a claim online for a few pounds.
Unfortunately, Vietnam is not a signatory to the Convention.
Vietnam has set up a parallel legal structure that, in the places concerned with airline liability, largely resembles the Convention, but it is a foreign law while you are in the UK, and for an Β£80 claim, it is not going to be sensible to raise a dispute.
airline who said they gave me a tag in Vietnam that release them from compensating for any damage
The only positive thing I can say, is that it seems under Article 167 of Vietnam's Civil Aviation Law, such a "tag" is null and void.
Art. 137 (1) Any agreement by the carrier with the passenger, the consignor and consignee on exoneration of the limits of liability referred to in paragraph 1 of Article 166 shall be null and void.
You can try writing back to their complaints department, but I think to be honest you are not going to get your Β£80 back. Your best bet is to discuss the matter with your insurer, or possibly raise a Twitter storm.