Flutter project implement flavour i am not able to install pod in iOS side

Question

i am multiple flavour implement in flutter project but flutter SDK update i am not able to install pod..its showing error

i have also delete podfile & podfile.lock & regenerate the podfile but same error show

Invalid plugin specification: EXCLUDED_ARCHS[sdk=iphonesimulator*]=i386

[!] Invalid Podfile file: no implicit conversion of nil into String.

from /Users/atpl/Documents/insuranceflutter/ios/Podfile:57

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unless File.exist?(copied_framework_path)

   FileUtils.cp_r(File.join(cached_framework_dir, 'Flutter.framework'), copied_flutter_dir)

end

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