First off, congrats on keeping your J7+ and A8 working through all these years! That's quite an achievement.
So, it's actually pretty normal for phone batteries to wear out, especially if they're used daily. 5 years is a pretty long time, so it's possible that your battery might be on the fritz at this point. I'd advise you to check if your back plate is slightly raised - if it is, your battery is bloated, and it is dangerous to keep using it.
That said, here are some options you have to move forward:
- Head to a Service Center for battery replacement, and any other repairs your device may need. Keep in mind that the service center will be charging for the repair and parts replacement.
- Deposit your tablet at a Service Center for proper e-waste disposal. If you discover that your battery is indeed bloated, you may deposit it at a Samsung Service Center so our team can dispose of the hazardous waste properly for you.
- Buck up for an upgrade. Your devices are getting old, and support for them may end soon. As you know, we recently launched the Galaxy Z and S23 series smartphones, plus we also have the more affordable A series lineup available as well! There's a ton of choices for you to experience a new mobile experience #withGalaxy - so let me know what you need and I can recommend the perfect device for you.
Let me know if you have any other questions!
It might be because the battery was completely drained. When that happens, it takes a while for it to store power again, especially with a battery as old as your A8's.
Glad to hear it's working as of the moment! Try running the diagnostics tool in your Samsung Members app on the A8 so we can have a better idea of what's wrong with your device :)