Issue with common maintenance for an apartment.

Hello, We bough a flat in Apartment on Mar-2016, Till that time builder used to take of maintenance, collected 1000/- later respective responsibility got moved to Owners, From there also they used to collect 1000/- as maintenance for around 15 mounts, after fulfilling monthly needs, we were able to accumulate some 55000/- funds, One fine day complete amount got used by a few owners-ofcourse for Apartment only, there after i.e/. from Feb-2018 they raised maintenance amount to 1500/- with out sharing justification details for this 50% hike in maintenance charges. They have taken 1000/- as maintenance from me till July-2018 and send back June+July months maintenance through watchman with out having word with me[On the same day i attended monthly meeting as well, in that meeting no one raised this point after meeting they simply sent back two months maintenance] , there after i keep on asking the reason for 50% hike and maintenance records to cross check whether 1000/- is not enough but unfortunately they refused to share the maintenance records as well. Finally we got a chance to go through on Feb-2019 (i.,e after a year), after checking them thoroughly we share our views that 1000/- would be still enough then why you are demanding 1500/- again no response. To make our dues clear i.e, from June-2018 to Feb-2019 (We are clear till MAr-2019 with 1000/- as maintenance amount) we paid common electricity bill and payment to Association towards garbage collection as owners are sending back paid maintenance amount to me. Now a few owners and builder are verbally abusing us like any things and enforcing us to pay 1500/- from Feb-2018, and threatening like they will cut power,water connection and lift usage to us, even we are worrying they may attack us physically in future meetings . Could some one please help me in how to proceed further and come out of this. Thanks in advance