[Python] PlotlyExpress not generating bar chart properly

I am trying to create a basic plotly chart:

import numpy as np
df = pd.DataFrame({"college_name":list("ABCD"),"in-state_tuition":np.random.randint(5000,7000,4),"out-of-state_tuition":np.random.randint(8000,15000,4)})

px.bar(
data_frame = df,
x = "college_name",
y = ["in-state_tuition","out-of-state_tuition"],
opacity = 0.9,
orientation = "v",
barmode = 'group',
title='Annual In-State Tuition vs Out-of-state Tuition',
)


but the result is incorrect, as it returns me bar chart of the same height:

I got the example from : https://plotly.com/python/bar-charts/

I am using the following versions: plotly: 6.1.2 numpy: 1.23.5

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