BLE scan in background not working for xamarin.ios

Question

App scans the BLE device(Mokobeacon) in foreground mode. Scan, connect and disconnect work well in foreground. Scanning using this.manager.ScanForPeripherals(CBUUID.FromString("FF01")) and devices available at void DiscoveredPeripheral(object sender, CBDiscoveredPeripheralEventArgs args) method. But scan will not start when the app is in background, when app comes to foreground, scan works and DiscoveredPeripheral hits, connect and disconnect will work. I'm using iphone 13.6 . Background options enabled in info.plist also(both bluetooth central and peripheral) .Scan works in both modes for android;no issues there. Is there any restriction for ios for not to scan in background? help appreciated...