Unable to eliminate last talbeviewcell (when search is empty) - ios

Question

I use this code to search for all files that are off in "review",
And there is a button to change "review" to "on". When "review" is changed to "on"(because the code only searches for "off"), the tableviewcell will disappear normally.
But every time the last stroke will not disappear(tableview can't find the file), you need to restart the app to clear the tableviewcell,
Why is this?
let db = Firestore.firestore()
db.collectionGroup("TWDBuy").whereField("review", isEqualTo: "off")
.order(by: "date", descending: true)
.addSnapshotListener { (snapshot, error) in
This is tableview
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return postArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "TWDBuyPGTableViewCell") as! TWDBuyPGTableViewCell
let post = self.postArray[indexPath.row]
let date = post.date
let dateFormatter = DateFormatter()
dateFormatter.calendar = Calendar(identifier: .iso8601)
dateFormatter.timeZone = TimeZone(identifier:"Asia/Taipei")
dateFormatter.locale = Locale.init(identifier: "zh_Hant_TW")
dateFormatter.setLocalizedDateFormatFromTemplate("yyyy-MM-dd HH:mm")
let dateStr = dateFormatter.string(from: date)
if postArray[indexPath.row].review2 == "未確認"{
cell.review2.textColor = UIColor(red: 255.0/255.0, green: 192.0/255.0, blue: 0.0/255.0, alpha: 1)
}else{
cell.review2.textColor = UIColor(red: 55.0/255.0, green: 163.0/255.0, blue: 152.0/255.0, alpha: 1)
}
cell.quantity.text = "數量："+postArray[indexPath.row].quantity+" USDT"
cell.coin.text = "匯入： TWD "+postArray[indexPath.row].coin
cell.address.text = postArray[indexPath.row].address
cell.network.text = postArray[indexPath.row].network
cell.email.text = postArray[indexPath.row].email
cell.review2.text = postArray[indexPath.row].review2
cell.uid.text = postArray[indexPath.row].uid
cell.useruid = post.uid
cell.useremail = post.email
cell.commentDelegate2 = self
cell.time.text = dateStr
cell.idimage.sd_setImage(with: URL(string: postArray[indexPath.row].ID5))
cell.deleteThisCell2 = { [weak self] in
self!.delete2(didSelectRowAt: indexPath, cell: cell)
}
cell.deleteThisCell3 = { [weak self] in
self!.delete3(didSelectRowAt: indexPath, cell: cell)
}
let settings = Settings.defaultSettings
.with(actionOnTapOverlay: Action.dismissOverlay)
.with(actionOnDoubleTapImageView: Action.zoomIn)
addZoombehavior(for: cell.idimage, settings: settings)
getUserPortfolio(didSelectRowAt: indexPath)
//刷新
self.usertableview.es.addPullToRefresh {
[unowned self] in
/// Do anything you want...
/// ...
/// Stop refresh when your job finished, it will reset refresh footer if completion is true
self.usertableview.es.stopPullToRefresh()
/// Set ignore footer or not
self.usertableview.es.stopPullToRefresh()
}
return cell
}
I have updated the tableview, and there is nothing in the snapshot. If the tableviewcell has a "review" off, modifying each "review" to on will reduce it normally, but the last one will not disappear (firebase "review" is all on)