How to skip the rounding of the time when it is coming exact hours and minutes in swift 4

I a working in swift 4, I have a scenario is rounding the time to nearest 5 minutes (like 11:12 AM – 11:15 AM). I am able to do that for this mentioned scenario. But here my problem is I should not round the time when it is "11:15 AM". Can anyone please help me to resolve this issue.Thanks in Advance.Please find my below code..

func getTimesData{
       let date = Date()
        let df = DateFormatter()
        df.dateFormat = "yyyy-MM-dd'T'HH:mm:ss'Z'"
        let dateString = df.string(from: date)
        let convertedDate = dateString.convertingStringToDate(date: dateString)
      
        let roundedDate = convertedDate.rounded(minutes: 5, rounding: .ceil)  //Here I am rounding the time.

        let dateAdded = roundedDate.addingTimeInterval(5 * 180)
}

The below code I am using for round the time which I get from StackOverFlow itself.

enum DateRoundingType {
    case round
    case ceil
    case floor
}

extension Date {
    func rounded(minutes: TimeInterval, rounding: DateRoundingType = .round) -> Date {
        return rounded(seconds: minutes * 60, rounding: rounding)
    }
    func rounded(seconds: TimeInterval, rounding: DateRoundingType = .round) -> Date {
        var roundedInterval: TimeInterval = 0
        switch rounding  {
        case .round:
            roundedInterval = (timeIntervalSinceReferenceDate / seconds).rounded() * seconds
        case .ceil:
            roundedInterval = ceil(timeIntervalSinceReferenceDate / seconds) * seconds
        case .floor:
            roundedInterval = floor(timeIntervalSinceReferenceDate / seconds) * seconds
        }
        return Date(timeIntervalSinceReferenceDate: roundedInterval)
    }
}

let rounded = Date().rounded(minutes: 5, rounding: .ceil)

let rounded = Date().rounded(minutes: 5)