35 duplicate symbols for architecture x86_64 clang: error: linker command failed with exit code 1

Question

I'm so frustrated... just cannot fix the error I mentioned in the title. What I tried:

• Cleaned Build Folder multiple times
• Deleted Derived Data multiple times
• Yes, I open the Workspace (not Project)
• changing 'No Common Blocks' from Yes to No
• pod update, pod install, ...
• searched for duplicates

No success so far.... But I think I see the problem:

It looks like there is another DerivedData Folder somehow but I deleted the entire DerivedData Folder multiple times (and also deleted it in the trash. So there cannot be another DerivedData file. Correct me if I'm wrong but it makes no sense to me :(

Or there is a problem with the "nanopb.build" pod thing.. idk :/ Does anyone has a clue how to fix this?

I actually don't even know what the nanopb thing is...

Greetings

Henning :)

EDIT:

Here is my Podfile:

   target 'huud' do
   use_frameworks!
    pod 'Firebase/Core'
    pod 'Firebase/Database'
    pod 'GrowingTextView', '0.7.2'
    pod "RAGTextField"
    pod 'SkyFloatingLabelTextField', '~> 3.0'
    pod 'NewPopMenu', '~> 2.0'
    pod 'LGButton'
    pod 'LocationPicker'
    end