How to amend an agreement - already signed a agreement for man power suppliers on head count basis payment

Dear colleagues, We have already signed a agreement for man power suppliers on head count basis payment, but contractors want to revise the payment value on which we too agree with that but existing agreement valid till 2022 what will do next for amend the agreement?

The parties to an agreement can amend the existing agreement to any extent by mutual consent. Refer to the existing agreement, mention the clauses of the agreement being amended, the revised clauses, the effective date of implementation of the revised clauses and get the signature of both parties.

A contract is a mutual agreement -consideration and consensus ad idem.
Once both parties want to make a change,then no issue at all.Just redraft and make changes and execute the changed agreement (contract)

In an agreement or work order the clause of amendment exists. Since the agreement has been signed by the both the party, you need to call the agency and discuss the matter. Explain why an amendment or inclusion of clause arises at this point and was due to typography error which noticed now. Therefore, only option is left to amend the contract or to scratch fully.