Error while training

[Stolaine]

I have created a model on the for text classification.
the dataset contains a numpy array saved as a .npz file .
When I train the model without K-fold validation - it starts training and performs each epochs.
But when I use K-fold validation - i am getting error saying "Cannot broadcast an array of size (825) to an array of size (826)". Also this error comes after I increase the number of folds from 2 to 10.

Can anyone help?