Charging issue

So for the last few days I've had issues where I go to bed at night with my phone at something like 27% and I put it on the charger to charge overnight... Then when I wake up the next morning, it is at 24% or something, almost as if it wasn't even charging.

After I thought this was an issue, I would monitor the charging moreso, in different outlets, with different chords, and sometimes when I plug it in to charge, it will start for a while, then stop, or charge all the way. Or sometimes I will plug it in and it wont charge at all. The charge icon shows up next to the battery, but the percentage doesn't even move.

I've tried hard resetting and restoring my phone (but I've only restored from a backup, because I have had sensitive data on my phone inside apps (like school schedules and etc that I have spent hours planning and mapping out, that I want to carry over to the next rendition)

Would anyone have any more suggestions as to what I should do?

Thank you!