Issue while using fit()

I was working on creating a pipeline using tpot, however I was facing the following issue

## Context of the issue

I'm using the following code within one of my modules of the workflow:
x_train, x_test, y_train, y_test = train_test_split(train_x.values, train_y.values, test_size=0.25)
tpot = TPOTClassifier(n_jobs=-1, verbosity=2, use_dask=True)
features = x_train.astype(float)
target = y_train.astype(float).ravel()
tpot.fit(features, target)

train_x, train_y are pandas dataframe with no null values and only numerical data

## Current result

Following is the error I have been getting after I run the above selection

ValueError: Error: Input data is not in a valid format. Please confirm that the input data is scikit-learn compatible. For example, the features must be a 2-D array and target labels must be a 1-D array.

Looking at the error I'm confused because my input is a 2d(features) and 1d (target) array respectively

## Note

1. I'm relatively new to data modelling and TPOT also, let me know if I have made a mistake while implementation
2. link to my source code: https://github.com/varshithvvs/ml_workflow
a. Use the develop branch for the latest commit where I was facing the issue, I haven't updated the master yet.
b. Issue can be found in workflow.py