Penalty for late filling of IT returns for nil income

I am housewife having only income of bank interest for Assessment Year 2018-19 & 2019-20 & 2020-21. I have last filed 5000 income return for Assessment Year 2017-18. Can i file now returns for last 3 Assessment Year showing bank interest income  in Dec 2020. Will i have to pay any penalty for late filling of IT returns for Assessment Year 2018-19 & 2019-20 .