My phone is slow

Although it is possible for hardware issues such as a bad battery to cause the phone to slow down as a safety measure, in most instances it's caused by software issues such as full memory, too many apps open, or a particular app that's hogging all the resources. Try running your phone in safe mode to see if performance improves, check your battery health to see if it's in need of replacement, and if your memory is close to being full, delete some apps or offload some pictures/videos to reduce the amount of memory being used and see if that helps.

Try out some of these suggestions then come back and let us know if anything helped; if not we'll see what other ideas we have that you can try.