Property owned by father and mother both name but after father death mother make will to only one da

Good day sir I have quary regarding property my father bought a land in Lucknow along with mother co owner for that land after father expired due to road accident 2007 then accident claim and official claim money used for construction ground floor till 2008 to 2009 after that 2015 i constructed first and second floor with my own earning along with loan taken on that construction i am first loan borrower along with mother name as 2nd co borrower but all EMI going from that date to till date with my bank account.now Feb 21 mother expired due to cancer which detected in 2019.during that period my self and my sister both are look after for her.i have two sisters one merriage with but after mother expired after that my sister saying that my mother constructed will and all property given to her name she still unmarried now sister saying left my house and want me to leave house but he already have one house and two plots also one land which only my mother name and also father job in up government after death of my father i provided that job for her bcs that time I was already working in merchant Navy . regarding will i have no idea when made and where made i was asking her show me will so that I can consult with legal advice but not provided till date .