I’m trying to retrieve information from a contract. Saving info works just fine and it communicates well but when I try to retrieve the info it give this error:
unable to cast object of type 'system.object' to type 'system.collections.IList'

public async Task<string[]> GetAllPatientIdsAsync() {
    var contract = _web3.Eth.GetContract(_abi, _contractAddress);
    var getAllPatientIdsFunction = contract.GetFunction("getAllPatientIds");

    try
    {
        var result = await getAllPatientIdsFunction.CallAsync<object>();

        if (result is object[] objectArray)
        {
            string[] idsArray = objectArray.Select(x => x.ToString()).ToArray();
            return idsArray;
        }
        else
        {
            MessageBox.Show($"Unexpected return type: {result.GetType()}.");
            return null;
        }
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message, "Error");
        return null;
    }
}

Here is the code of the Contract:

// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;

contract PatientRecord {
    struct Patient {
        string id;
        string name;
        string medicalHistoryHash;
    }

    mapping(string => Patient) private patients;
    string[] private patientIds; // Array to store patient IDs

    // Event to log the addition of a new patient
    event PatientAdded(string id, string name, string medicalHistoryHash);

    // Function to add a new patient
    function addPatient(
        string memory _id, 
        string memory _name, 
        string memory _medicalHistoryHash
    ) public {
        // Check if the patient already exists
        require(bytes(patients[_id].id).length == 0, "Patient already exists");

        // Add the patient to the mapping
        patients[_id] = Patient(_id, _name, _medicalHistoryHash);
        
        // Add the patient ID to the array
        patientIds.push(_id);

        // Emit the event
        emit PatientAdded(_id, _name, _medicalHistoryHash);
    }

    // Function to retrieve a patient's information
    function getPatient(string memory _id) public view returns (string memory, string memory) {
        // Check if the patient exists
        require(bytes(patients[_id].id).length != 0, "Patient not found");
        // Retrieve and return the patient's information
        Patient memory patient = patients[_id];
        return (patient.name, patient.medicalHistoryHash);
    }

    // Function to update a patient's medical history
    function updateMedicalHistory(string memory _id, string memory _newMedicalHistoryHash) public {
        // Check if the patient exists
        require(bytes(patients[_id].id).length != 0, "Patient not found");

        // Update the patient's medical history
        patients[_id].medicalHistoryHash = _newMedicalHistoryHash;
    }

    // Function to retrieve all patient IDs
    function getAllPatientIds() public view returns (string[] memory) {
        return patientIds;
    }
}

I kept asking ChatGPT but it stopped giving the same error, I should be able to retrieve the String IDs in the list