Why do you want to do a hard reset but not a soft one?

There terms are vague, but "soft reset" basically means a forced restart. Usually just press the power button down until the phone restarts (may be 10 seconds or more - ignore any prompts on the screen). If you have a removable battery just pull the battery out instead - if you can do that then keep it out for a minute or two while you are there (ensure everything is discharged). Though in most cases just restarting the device will do as well.

A hard reset I understand to be a factory reset, i.e. erase all user-installed apps and all user data (does nothing to the system software). That's the thing you'd want to avoid if you can.

The best solution however is to identify what is causing the power drain and deal with that. The system settings can tell you something about power usage, apps like GSam Battery Monitor can give you more details. If the cause is a rogue app holding the phone awake you want to know which one.

Of course if you are living on the edge of network coverage, constantly losing signal, searching and reconnecting (or dropping from 4g to 3g then switching back) that's going to drain you quickly no matter what you do (apart from changing network).

 

Soft-reset is our friend @InternetIsUnsafe

 

maybe you are looking at the wrong app. there is a possibility that another one is draining the phone. it is hard to say. have you tried just rebooting?

 

When checking Settings >> Battery you've mentioned it states the battery is at 100% after charging but it might be more revealing as to which app is draining your battery overnight to instead check your Settings >> Battery menu in the morning when the battery is depleted to see which app, or apps, might be the possible source of a problem.

 

Exactly: the battery menu will tell you what has used power in this charge cycle. So you need to let it run fairly low and then look at it.

If that isn't enough then try a better battery monitor app.

 

In this case I believe that you need a HARD reset to get rid of some third-party apps that kill the battery.

 

If there's no apps or services listed that might help determine what to look into then you'll have to start digging a little deeper. Before you go to sleep enable Airplane mode on your phone and then in the morning check to see if the battery is still being depleted in a similar way.
Airplane mode turns off all network connectivity -- WiFi, cellular (no phone calls, no texting, no mobile data), and Bluetooth -- so see if this makes any difference in battery depletion.

 

If the battery is still getting depleted the same way overnight with Airplane mode enabled, another thing to try is start up your phone in its Safe mode before going to bed and see if that makes any difference. When running in Safe mode it's only the base Android operating system, no third-party apps/services will be auto-launched at startup.
If battery life is noticeably better in the morning than that indicates some issue with an app you've installed. Of course now it's a matter of figuring out just which one. But typically third-party apps will be showing up normally in the Settings >> Battery menu if they are using up battery too much, so it is odd that you're not seeing anything listed there as out of sorts.
If the battery is still draining as quickly in Airplane mode and the same in Safe mode too, I'm running out of ideas. A Factory Reset 'might' help, just be sure you're got a backup of all your saved data first. You might want to use Samsung's Smart Switch utility, it'll make doing a full backup and restore less of a hassle.
https://www.samsung.com/us/smart-switch/
Otherwise, there is a chance the battery itself is starting to fail. Your J7 is a couple of years old now isn't it? That's a little early for most smartphone batteries, they do lose the ability at an increasing rate as they age. But usually this isn't so noticeable for another year or two. Do you typically charge your battery often or is it a matter where you regularly run your battery down past 15% or so on a regular basis?

 

It might help in the future if you discontinued using 'soft reset' and 'hard reset'. As @Hadron previously pointed out, they're somewhat vague references. Both are more generic terms that can be interpreted differently depending on the situation. If you did a 'soft reset' that might be taken to mean restarting your phone, or not. When you refer to doing a 'hard reset' I'm taking that to mean you did a Factory Reset solely by reading through your description, but of course that's not definitive at all since 'hard reset' has so many different meanings.
If you did do a Factory Reset, that's going to wipe all user saved data (files, documents, app settings/config files relevant to your apps) but it does not affect the installed, Android operating system. Typically an Android install includes some default wallpapers, they were there when you first set up your phone and because they're essentially part of the OS they'll remain before and after a Factory Reset. Were you using one of the included wallpapers or did you have something like a photo from your own personal files selected as your wallpaper background?

 

It may also be that you have some backup options set that restored some stuff when you logged into your account again.

 

"soft reset" and "hard reset" is something I used to do on my Commodore 64. A soft reset kept the Basic program in RAM, while a hard reset cleared all the RAM. How that relates to an Android phone, not quite sure.

 

The "Cloud" has your info. Hard-Reset takes you to the "Cloud".
Soft-Reset is still your friend.

 

This is the proper method to hard reset Android phones and iPhones