Custom cell not showing in Table View-Xcode

I have made a custom cell and using its .xib to show in table view. But the this cell is'nt showing in table view.While other custom cells are fine.

Cell Controller:

import UIKit

//Protocol to add action on button click
protocol ChatLinkButtonDelegate: class {
    func chatLinkClick(cell: ChatBankController)
}


class ChatBankController: UITableViewCell {
    @IBOutlet weak var btnseemore: CustomUIButton!
    @IBOutlet weak var year: CustomUILabel!
    @IBOutlet weak var anwser: CustomUILabel!
    @IBOutlet weak var month: CustomUILabel!
    @IBOutlet weak var interest: CustomUILabel!

    var delegate: ChatLinkButtonDelegate?

    override func prepareForReuse() {
        super.prepareForReuse()
        self.delegate = nil
    }
    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
    }
    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)
        // Configure the view for the selected state
    }

    @IBAction func btnChatLinkClick(_ sender: Any) {
        self.delegate?.chatLinkClick(cell: self)
    }
}

Table View controller to load and show data: Registration:

cell = UINib(nibName: "ChatBank", bundle: nil)
            self.tbChat.register(cell, forCellReuseIdentifier: "ChatBankCell")

Loading cell to tableview:

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

                    let cell:ChatBankController = self.tbChat.dequeueReusableCell(withIdentifier: "ChatBankCell") as! ChatBankController
                    cell.anwser.text="fine"
                    return cell

                    let cell = UITableViewCell()
                    return cell
    }