Indigo Airlines — compensation for a late flight

We bought 3 return turkish airways tickets from tel aviv to delhi. The ticket numbers are[protected], [protected] and[protected]. Our return flight from delhi to istanbul was codeshared with indigo. Flight 6e11on august 16, 2019. It arrived late to istanbul, and as a result we were late to board the connecting turkish airways flight to tel aviv. The turkish airways representative wrote to air indigo asking them to get us alternative tickets, but was ignored by air indigo. So we had to buy the tickets by ourselves.
The first available seats we could get were business tickets in turkish airways. We had no choice but to buy these tickets since neither indigo or turkish airways in istanbul compensated us.
I have receipts of the tickets - they were 815 usd each.
Please refund us