Neural Net: Combined features worse than separate features

I created a dataframe with 3 columns, feature_1, feature_2, and target, with the goal of having feature_1 and feature_2 predict the target. I standardized feature_1 and one-hot-encoded feature_2 (which has 100 categories and therefore creates 100 columns). I know for sure that feature_1 and target are correlated and so is feature_2 and target. The target is numbers from 1 to 10 and I create a correlated categorical (feature_2) variable by making a portion of the categorical values map perfectly with the target, for example, when target is a 3, set feature_2 to "A". Creating a model with only feature_1 vs target I get val_loss of 7.60.