Crowd Sale Contract Issue while minting token

I am currently working on a crowd sale contract, But I am having an issue with a function as the list of the error and the code of the function is attached, I need someone to tell me that what is happening in the code and how can i resolve the error that I'm facing in the code. Solidity version ^0.5.0

Code:

function _finalization() internal {
    if (goalReached()) {
        ERC20Mintable erc20Mintable = ERC20Mintable(token);
        //getting the total tokens that are been minted yet
        uint256 alreadyMintedToken = erc20Mintable.totalSupply();

        //tokens of the final total supply
        uint256 finalTotalTokenSupply = alreadyMintedToken
            .div(tokenSalePercentage)
            .mul(100);

        foundersTimelock = new TokenTimelock(
            token,
            foundersFund,
            releaseTime
        );
        partnersTimelock = new TokenTimelock(
            token,
            foundersFund,
            releaseTime
        );
        foundationTimelock = new TokenTimelock(
            token,
            foundersFund,
            releaseTime
        );

        //we will have the tokens that the founder will get
        erc20Mintable.mint(
            address(foundersTimelock),
            finalTotalTokenSupply.mul(foundersPercentage).div(100)
        );
        erc20Mintable.mint(
            address(partnersTimelock),
            finalTotalTokenSupply.mul(partnersPercentage).div(100)
        );
        erc20Mintable.mint(
            address(foundationTimelock),
            finalTotalTokenSupply.mul(foundationPercentage).div(100)
        );

        erc20Mintable.renounceMinter();
        // Unpause the token

        ERC20Pausable erc20Pausable = new ERC20Pausable(token);
        erc20Pausable.unpause();

        erc20Pausable.renounceOwnership(wallet);
    }
    super._finalization();
}

Error 1:

Explicit type conversion not allowed from "function () view returns (contract IERC20)" to "contract ERC20Mintable". ERC20Mintable erc20Mintable = ERC20Mintable(token);

Error 2:

Crowdsale.sol:179:46: TypeError: Invalid type for argument in function call. Invalid implicit conversion from function () view returns (contract IERC20) to contract IERC20 requested.
foundersTimelock = new TokenTimelock(token,foundersFund,releaseTime);
^---^

Error 3:

Crowdsale.sol:179:28: TypeError: Type contract TokenTimelock is not implicitly convertible to expected type address. foundersTimelock = new TokenTimelock(token,foundersFund,releaseTime);