local variable 'i' referenced before assignment

[fht-ht]

Traceback (most recent call last):
File "E:/fht/translatotron/train.py", line 375, in
args.warm_start, args.n_gpus, args.rank, args.group_name, hparams)
File "E:/fht/translatotron/train.py", line 328, in train
hparams.distributed_run, rank)
File "E:/fht/translatotron/train.py", line 215, in validate
val_loss = val_loss / (i + 1)
UnboundLocalError: local variable 'i' referenced before assignment

How can I solve this problem?