Hello @350541732 - When you are using a pod you should not have to set the header search path manually. This was required by a few folks earlier in the thread because they were not using CocoaPods.
In this case, you should remove any manual header search paths. You might even want to manually edit the project.pbxproj file and ensure there are no occurrences of HEADER_SEARCH_PATH present. Most importantly, when you run pod install you should not receive any warnings about the project HEADER_SEARCH_PATH overriding the pod settings.
It’s worth mentioning that I have tested this under XC9, it is working fine, and that every case where this error has come up so far has been the result of improperly configured header search paths.
If you are continuing to have trouble you can post a sample project that reproduces the issue under a permissive open source license up to GitHub, then post the URL here.