The contractor and labours have no right to enter your premises without your permission. In this situation, you should lodge a complaint against them for the offense of house trespass. Simultaneously, you can also inform the Station House Officer (SHO) at the local police station about this incident.
If there is a possibility that this dispute may escalate and disrupt peace and tranquility, the SHO can submit a report to the Magistrate, requesting them to have the individuals involved in the trespass post a bond under Section 107 crpc. This bond will remain in effect for up to one year. If they continue to obstruct or interfere with your property, the magistrate can forfeit that bond and initiate appropriate legal proceedings against them.