Ford India — Ford India and Gautam budh ford engineering fault

I bought ford in 2016, from starting it never worked properly litle issue here and there, major breakdown happened in 2019 when a warning light came and when we took it to service, we got to know that engine oil and coolant got mixed and engine for sealed, so engine got replaced, very recently my vehicle for services on 20th July 2021 but Gautam budh service guys was careless after mentioning battery in G so batteru gur replaced with one month and starter motor has to be replaced next one month when it was working fine,
2 weeks back, warning light came for veichle temp becoming hot, we towed it to service center now these people are coming with estimate of at time 45k at time 2.5 lakhs... as they say again engine oil and collant got mixed, This is absolutely their engineering fault, when warning light came, we immediately get it towed then how it get mixed