Error received when applying example code for trainNetwork with numerical features to 2 d feature data, with integer classification codes

I receieved the following error when running the example code for trainNetwork with numerical features on 2d numerical feature data with integer classification codes.

Error using trainNetwork

Invalid training data table for classification. Predictors must be in the first column of the table, as a cell array of image paths orimages. Responses must be after the first column, as categorical labels.

Error in DLNetwork2 (line 143)

[net,info] = trainNetwork(tblTrain,layers,options);

Error in TestReluCVM (line 213)

[net,info,Ypred,Ytest] = DLNetwork2(X',Y);

NOTE: The data was not image data. X was (n,2) numeric data; Y was (n,1) integer classification codes.

I don't understand how to fix the error.

Thank you.

Linda Ness