Couldn't find 32-bit or 64-bit versions of the Android toolchain

hi its empty scene i try to package andoid all this happen:

UATHelper: Packaging (Android (All)): Program.Main: ERROR: AutomationTool terminated with exception: ERROR: Couldn't find 32-bit or 64-bit versions of the Android toolchain
UATHelper: Packaging (Android (All)): Program.Main: AutomationTool exiting with ExitCode=1 (Error_Unknown)
UATHelper: Packaging (Android (All)): BUILD FAILED

how can solve this ?

redownload ndk its work thanks

didnĀ“t work for me. Is there anyone who can give a step by step explanation through the process?