Follow the steps below to reactivate a contract.
Select Customer Setup > Codes... > Contracts.
Place a check in the Include inactive codes box to include inactive contracts in your search results.
Use the Show All button to view all contracts. Or use the Search field to further drill down your search.
Select the Contract
Click OK when the “This contract is currently inactive.” pop-up displays.
Uncheck the Make this contract inactive checkbox.
Click Save.