Sale Document of flat Tampered

My mother has tampered with the sales deed of her flat. The flat was purchased by my mother (in her married name) with her income (my parents were not living together) in the year 1993 on a joint name, my moms name and my name (I was a minor at that time). The following year my mother divorced my dad. Five years down the line my mom went back to her maiden name (through a government gazette) while I (who was 18) changed my name too and took my mother’s maiden surname and a different name. Sometime along this time my mother erased her married name and signature from the sale deed and rewrote her name and signature to the maiden one. She also erased my name and left it blank. She then submitted her name change gazette to the society and changed her name in their records.