Training not starting with pre-trained model with "include top layers" true

With this DL model

the following error is displayed when starting the training:

The DL model is validated Ok in the Model tab.

Can you try removing Flatten_14 (since VGG16_13 output is already flattened) ?

Did it and it is working fine. I forgot to remove the Flatten layer which is not needed here. Thanks for the help.