Delhivery — False guarantees, delay in delivery

I registered for the express delivery option at Delhivery. I gave the parcel on 2nd of October 2021, as 7th of October 2021 was my Anniversary. At first, estimated date was 7th, then for 3 days the parcel did not move out of Ahmedabad. The estimated date then became 8th October. I started raising constant issues, but, no one contacted or replied properly or understood the fact that is was an urgent requirement. The only 'promise' they made was that they will deliver it on 8th. So, to top that off, today i.e on 8th October, they changed the delivery date to 9th October, in spite of my constant and ardent requests. Probably express means delay in Delhivery language.
I request a full refund, though it will not help with my anniversary surprise being ruined, but, it will still feel a bit good.