Battery faulty

Service received from sales person was great but once the transaction was completed no further help was provided. I bought a vw up 2016 on 3 December 2025 at the Epping Branch . Paid this vehicle in cash , went to collect the vehicle the next day , as i was driving home i stopped at my sister when i was about to leave the car didnt want to start i informed the sale person he said i should jump start the car , which i did The sale person then said he will speak to his manager regarding this issue with the battery .He advise me i can buy a new battery which i did . I let customer services know about this faulty as advised then then told me the car was under warranty hence they cannot assist me with the refund of the battery number i asked the sale man if the car has a warranty he said no , i resend an email to customer services stating the car has no warranty up to today no response , how can they sell a car which needs to be jumped start everytime you must drive and for a female is absurd ,i would understand if they said in the report that the battery was faulty i would totally understand but nothing was mentioned that the battery was faulty