B2 extended stay wasn't approved for 6 months

My in-laws came to united states on sep 18 2021 september with B2 visa and they are valid to stay until March 17th 2021 and we applied for I539 extension in the month Feb 2022 requesting for additional 6 months due to covid situation. The I-539 was pending until last week and it’s approved on 2023/04/26, stating valid until only 2022/06/14(for both of them) and My Father-in-law travelled to India on 2022/06/14 and where as my mother in law travelled to india on 2022/07/20.

It looks the Approval notice was based on my father in law travel and they didnt consider my mother in law travel.

Could some one please assist if there will be any issue in the future at port of entry next time ? Anything need to be followed up today ?

A few days of overstay may not be big deal. Your MIL can explain the situation if asked by the CBP at port of entry the next time she visits.