Turn off data and just use it for calls and SMS and it’ll last even longer (just like old Nokia phones used to).
Android used to let you disable 3G/4G data and just limit the phone to 2G data - - low bandwidth but adequate for syncing email and other tasks, much lower power usage. Unfortunately that option seems to have been removed.
That's because 2G networks are shutting down (together with 3G ones) and 4G/LTE ones are moved to lower, more efficient, frequencies previously taken by GSM.
Disabling 4G these days can often be counter productive for signal strength and battery life.
Android used to let you disable 3G/4G data and just limit the phone to 2G data - - low bandwidth but adequate for syncing email and other tasks, much lower power usage. Unfortunately that option seems to have been removed.