The button inside a button seems to reset the whole app.Why?

Using Streamlit

Topic		Replies	Views	Activity
Press a button do something then press another button do something else Using Streamlit	3	2299	May 13, 2022
Streamlit widget dependency Using Streamlit	8	3258	January 12, 2022
Streamlit with session_state Using Streamlit	7	3592	August 9, 2021
Can`t handle correctly with buttons Using Streamlit	2	2066	November 19, 2021
Part of page is getting refreshed on dropdown selection Using Streamlit cache	13	13102	February 8, 2022