Unable to merge android manifests?

Hi there, I've been developing a VR app for Android using the gvr-unity-sdk-0.8.1, and on Unity 5.6.1, yet every time I try to build the .sdk I'm getting the error "Unable to merge android manifests". I notice the error comes up as the progress bar hits "Merging AndroidManifest.xml files", but I'm not really sure what to make of this.

I've traced the locations of any AndroidManifest.xml files on my PC but I don't know whether I should be deleting some or what. Coping with these sort of errors really isn't within my expertise so any help would be appreciated. I've already done some searching on this but every solution I've found so far hasn't been fruitful

Thanks