com.google.mlkit.vision.text.TextRecognizer com.google.mlkit.vision.text.internal.zzb.zza() on a null object reference

I'm trying to implement mlkit for text recognition.

But while using

val recognizer= TextRecognition.getClient()

Throws this expection

com.google.mlkit.vision.text.internal.zzb.zza() on a null object reference