Apple watch app, App store submission issue

I developed a companion apple watch app for our iOS app. I was able to successfully archive the build but I am getting this error mail from Appstore connect when submitting the build - 

ITMS-90562: Invalid Bundle - One of the nested bundles is built for a platform which is different from the main bundle platform. Please make sure that all bundles have correct platform specification.

Any idea how to fix this issue?

Apple watch app, App store submission issue
 
 
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