Hello there HimelJilon,
We understand you're having some issues connecting to the same Wi-Fi network. Let's take a closer look as we do our best to provide some additional insight.
To get started, does the same thing happen with other Wi-Fi networks as well, or just this one in particular? If it just happens with this specific network, have you already tried restarting your modem/router?
In the meantime, we'd suggest starting with the rest of these steps: If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network If you still need help after trying those steps, be sure to also review the Get more help section before contacting Apple Support if needed.
We hope this helps get you pointed in the right direction.
Take care.