Just visit income tax website n register ur self then u ll see compliance section there you will find why this message is generated, do not panic, if ur income is below threshold limit u can state it and submit, if nri, u r not required ITR if the income is not earned in India, you need to specify it.
even i got the same msg .. for 2017-2018 .. but in that year my mother passed away , and coz of that her fd amount had to transfer in my account ... so my pan card flagged coz of this