sounds strange you only got there today and its dead.. Hope its something simple..
Our 2019 LC started normally to take us up the road 21km. Came back from shopping 20mins later and car wouldn’t start. RACQ called and he checked voltage - 12.7. OK, he said, start it. He called out stop after 1-2 secs. He said he could smell the electrolyte where it was boiling, and the cranking amps was 68 CCA.
Basically the OE 2 year old battery was rooted. A new battery was installed by the RACQ guy.
Like all my batteries, it was always on trickle when parked in the garage.
Toyota weren’t interested, telling me that to get any sort of pro-rata warranty after the initial 12mth, I would have had to have brought the vehicle into their workshop for their technicians to test, prior to anyone else ‘interfering’ with it.