ValueError No data provided for dense_7 Need data for each key in dense_7 dense_8 dense_8

This error occurs when trying to fit a neural network model and the input data is not provided for all the layers in the model. In this case, the error message indicates that data is missing for the layers 'dense_7', 'dense_8', and 'dense_8'.

To fix this error, ensure that the input data is properly formatted and provided for all the layers in the model. Check that the input shape matches the expected input shape of the first layer and that the number of output units matches the number of input units of the next layer. Additionally, make sure that the data is properly preprocessed and normalized before feeding it into the model.