Hey,

Im still learning how to write my smart contracts and have got stuck with a weird problem i dont fully understand

I have a function in a contract that looks like this

function getOwner(uint deviceId) public view returns (address) {
return deviceToOwner[deviceId];
}

It works in the test case when I test it like so
const owner = await deviceFactoryInstance.getOwner(deviceId);
expect(owner).to.equal(accounts[0]);

However, when I try to fetch this from the client using web3.js I get an error
const index = 0
const owner = await deviceFactory.methods.getOwner(index).call();

Could anyone help explain what im doing wrong?