I want to delete a message from a chat using messageKit

Question

Use messageKit with Firebase When I delete any message in the chat using long press, it gets deleted in front of me, but when I leave the chat and come back, it is not actually deleted.

    override func collectionView(_ collectionView: UICollectionView, canPerformAction action: Selector, forItemAt indexPath: IndexPath, withSender sender: Any?) -> Bool {
           
           if action == NSSelectorFromString("delete:") {
               return true
           } else {
               return super.collectionView(collectionView, canPerformAction: action, forItemAt: indexPath, withSender: sender)
           }
       }
       
   override func collectionView(_ collectionView: UICollectionView, performAction action: Selector, forItemAt indexPath: IndexPath, withSender sender: Any?) {


   
           if action == NSSelectorFromString("delete:") {
               // 1.) Remove from datasource
               // insert your code here
               self.mkMessages.remove(at: indexPath.section)  // Here it is deleted
               // 2.) Delete sections
               collectionView.deleteSections([indexPath.section])
           } else {
               super.collectionView(collectionView, performAction: action, forItemAt: indexPath, withSender: sender)
           }
       }

extension MSGViewController: MessagesDataSource {
    func currentSender() -> SenderType {
        return currenUser
    }
    
    func messageForItem(at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> MessageType {
        return mkMessages[indexPath.section]
    }
    
    func numberOfSections(in messagesCollectionView: MessagesCollectionView) -> Int {
        return mkMessages.count
    }