Is there any way to avoid penalty for not filing ITR in 2019 along with schedule FA?

A senior citizen who is also a US citizen became Indian tax resident in 2019 (based on more than 182 days and she does not qualify as RNOR) Her income was less than 3 lac so she thought she is not required to file ITR.

But than we found - because she has a USA bank account - she was required to file ITR and disclose that foreign bank account(asset) This bank account had peak amount during the year 2019 was only about $500.

I understand that there is a penalty for not filing ITR and not disclosing Foreign asset under Income tax law She can prove the source of funds was legitimate (it was her son who deposited money in to her account as gift) So I don’t think black money act will apply here.

So under IT act - what is the penalty for not filing ITR and filing schedule FA ? And is there any way to avoid that penalty?