Extended hours orders get cancelled at 4 pm

It appears that if i place an extended hours order prior to 4 pm it automatically gets cancelled at 4 pm.
I’d like my order to last till the end of extended hours trading. What am i doing wrong?

My request looks like this: {“symbol”:“NVDA”,“qty”:1,“side”:“sell”,“type”:“limit”,“time_in_force”:“day”,“limit_price”:553.36,“client_order_id”:“df0b4165-f06f-40d3-b493-9a580593163d”,“extended_hours”:true}

Thank you in advance