Flutter Doctor

سلام
ببخشید میشه بگید مشکلش چیع؟؟؟
وقتی flutter doctor رو میزنم این متن رو نشون میده:

C:\Users\msk>flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.12.13+hotfix.9, on Microsoft Windows [Version 10.0.18362.30], locale en-US)
[!] Android toolchain – develop for Android devices (Android SDK version 28.0.3)
X Android SDK file not found: C:\sdk\build-tools\28.0.3\aapt.
[√] Android Studio (version 3.6)
[!] Connected device
! No devices available
! Doctor found issues in 2 categories.
C:\Users\msk>

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