Pension deduction by Employer

My mother-in-law (MIL) is currently getting family pension from an Electrical Distribution unit that is on a public-private-partnership model. My father-in-law expired in 2017. After death of husband, MIL was getting normal pension. But the company mistakenly forgot to convert it to family pension and instead paid MIL full pension for 2 extra years. After realizing their mistake, they made up a schedule and started deducting money (50% of the payments) from her pension payments without any notification to MIL. The problem MIL already paid higher income taxes due to the extra payment (to the tune of 1-3L). The company now says it is not their problem and they have to recover the extra amount. Can the company really do whatever it wants? MIL suffered losses because of their mistake. Now she has to control her monthly expenses because of their mistake. Overall we have two concerns 1. Pension was recovered without any notification to the receiving party. As a result, MIL kept her normal expenses without realizing the company forgot to adjust pension amount and she was spending more than she should. 2. Shouldn't the company compensate for the losses due to extra income tax paid by MIL? If the company would have notified on time, maybe something could be done. But you cannot amend returns after 1 year.