Wrap HBAR for WHBAR

import { 
  ContractExecuteTransaction,
  TokenAssociateTransaction,
  Hbar,
  HbarUnit,  
  .. 
} from '@hashgraph/sdk';

//Client pre-checks:
// - WHBAR token is associated

const depositHbar = Hbar.from(depositAmount, HbarUnit.Hbar)
    
await new ContractExecuteTransaction()
 .setContractId(whbarHelperContractId)
 .setPayableAmount(depositHbar)
 .setGas(gasLim)
 .setFunction('deposit')
 .execute(client);