Cannot build model

[at3e]

Hello,
I am new to fairseq. I am trying to use the fairseq-train method to finetune the Wav2Vec2 model. When I run :
$ fairseq-hydra-train
distributed_training.distributed_port=$PORT
task.data=/path/to/data
model.w2v_path=/path/to/model.pt
--config-dir /path/to/fairseq-py/examples/wav2vec/config/finetuning
--config-name base_100h

An error occurs due to None type target dictionary while building the w2v model. How Should I pass the dictionary parameter?