OnePlus India — Repair service

I have given my mobile for repair on 13th October and today is 15 November till now i have not got my device back.i have made total 3 calls in oneplus service Center in first call they told that you will get your mobile on before diwali.Second call was made on 29 October in which I mentioned that i am going out of Mumbai on 17 November so please can i get my mobile before 17 then they told sure Sir you will get your mobile on 15th November but today when i again made call they told that sorry sir the mobile is now also in repair service we need more time.Almost a month has passed.So I thought I should make a complaint.So i call the oneplus customer complaint and now they are saying that i have made wrong claim in which i have to pay although it is in warranty period.Now they are saying that you will get your mobile in 4 to 5 days without repair.You will have to claim repair request again.Now i am going out of Mumbai. I don’t know what to do.I got to know that i have made wrong claim request when i made call.Before this i have made 3 call in that they never mentioned that they told that you will get your mobile repaired.And after 1 month they are saying that the claim is wrong.