Harassment by Neighbors in apartment

Dear advocates/lawyers, We live in an apartment (owner) which has no common walls & we've been living peacefully for more than 6 years. Recently, we purchased a medium sized shoe rack with doors to keep it closed & clean which we placed in our corridor, adjacent to our flat, in a specific corner (falls between two flats) which isn't obstructing anyone's pathway/movement (I wish I could share a photo here to show the same). Please note that all other residents in our apartment has made similar arrangements including the said neighbor (they've used a different corner space). Since the day we placed our shoe rack, our neighbors have been harassing my parents/me, my dad is a senior citizen & mom has health issues. Finally, with the involvement of our society's MC, we both came to a mutual agreement that; we will remove the shoe rack & moved it to a different spot & the neighbors were supposed to give a written apology for the uncalled for harassment. We took about 2.5 months to get the work done as we had to rely on our interior designer from whom we've got the shoe rack built for a custom size to fit into the corner space. We've kept our side of the promise & now the neighbors deny to apologize to my parents & more over they called police saying that we don't respect them, etc. They've also publicly posted about the complaint in a Whatsapp group which has all flat owners. During the meet involving MC, the guy from next door was about to physically assault my father but one of the MC member stepped in between & the next door guy was stopped. My parents have been having sleepless nights, feel scared while walking on the corridors as ours is a corner flat & we have to cross neighbors house to step-out/in from the apartment. Due to Covid & WFH, I have been living with my parents & I could witness this incident. After the offices open, I will have to move out of the house again & go to a different city as my job requires me to & I don't feel comfortable leaving my parents alone back at home anymore. What can I do to ensure that if something similar happens again in future then we have the upper hand? And, what can I do about the mutual agreement where we have fulfilled our side of the bargain & the opposite party denies? The problem here is, the president of the society is a close friend of my neighbor & all the decisions are taken in favor of my neighbors only. During the MC meet, the president himself was speaking in favor of the neighbors complaint & just wanted us to meet their demands, where as other MC members who were present they patiently heard both side of the complaints. Now that their demands have been met, the President denies to help us keep the other side of the agreement. The said neighbors have similarly had fights with various other residents in our society over the past few years. Please suggest the best way forward. Sorry for the long story, but, I wanted to give complete info to get better inputs.