"3 Times Battery breakdown in 1 week - Poor quality for money"

I did rent a car through Sunnycars at the airport of Kos in July 2019.
The car I received wasn’t well maintained.
In one week time the car has been broken 3 times. After driving a couple of kilometers and letting the car on the parking the power of the battery went down.
When I became nervous after the third incident, the person of the customer service was brutal and told me that I didn’t use the car properly and that I was responsible for the battery break.
I really not recommend the services of Auto Bank because they aren’t réalisable at all and the way they are treating customers is not professional at all.