Why is my updating taking forever to update?

You must have a stable Wi-Fi connection.

Or connect to a PC with the latest version of iTunes installed.

Charge the battery to 50% or higher.

Turn off Battery saving mode.

Don't use a Hotspot.

Don't use VPN.

And make sure you have enough free space.

You didn't read my reaction.

DON'T use a hotspot.

It’s the same thing for me I have been trying to update my IOS 15.3 for about 3days now and I have done everything you asked but is taking forever to download