Firebase error while configuring app - unrecognized selector sent to class

Earlier, I have faced the same issue, I fixed the issue by reinstalling pod.

Please refer to the below-mentioned steps to resolve the issue.

Please make sure that you have added Add two-parameter in Other Linker Flags.

$(inherited)
-ObjC

Cocoapods:

Just install cocoa-pods again in the project. Please refer below command for remove and install pods.

Remove all Framework from project using below command.

pod deintegrate
pod clean

- Install framework using below pod command

pod install

Manual:

If you have added framework Manual in the project then remove it and add it into the project again.

Issue:

You have faced reference issue in your project (framework not found at Specific Directory).

Hit the Clean and Build project. Everything worked as expected

Make sure GTMNSData+zlib.m from the GoogleToolboxForMac pod is still being built and linked into your app.

Make sure that -ObjC and -framework GoogleToolboxForMac is in the Link log: