Born and brought up in Guwahati, she began playing badminton at the age of seven, and trained at the Assam Badminton Academy under Indonesian coach Edwin Iriawan and India's Suranjan Bhobora, she was also coached by Pullela Gopichand for the Asian Games.

[3] She was the gold medalists at the 2019 South Asian Games in the women's singles and team events.

At the 2019 South Asian Games, Ashmita won the gold medal in the singles event by defeating compatriot Gayathri Gopichand and then in the team event by defeating team of Sri Lanka in the gold medal match.

At the Syed Modi International, Ashmita gave a walkover in the first round to compatriot Malvika Bansod.

At the Swiss Open, she entered as a wildcard and reached the second round before losing to seed no.8 Kirsty Gilmour 18–21,20–22.