MacBook Air Randomly Shuts Off When Unplugged

I believe my MacBook Air is a 2017 model.

So, this probably started a couple days ago. I usually have my laptop plugged in all day, which I realize is probably not recommended. But I have also been unplugging it at night and allowing it to go into sleep mode on its own. I rarely if ever do a full shutdown. Starting about two days ago, I will wake up to find the MacBook completely off, on it's own. I found this strange, and have attempted to see how it behaves when not on its charger.

I unplug the laptop, and let it rest on its own. It will either turn off immediately when unplugged, or stay on for around 15 - 20 minutes before instantly shutting off no matter what is being done on it. My battery says it is at 100%, and this last time I managed to get the battery to drain to about 80% before it, again, shut down on its own.

I have googled many solutions, and attempted many things having to do with PRAM and SMC. My MacBook Air has in the past required a new battery when the old one was failing, and I had a new one installed about a year and a half ago. As I said, I do leave the thing on very frequently and on its charger most of the time. The battery tells me it is in Normal condition, and like I said charges to 100%. I have seen with the old battery that it would give me a warning if it was failing, and required replacement. This one hasn't done that.

Battery Information:

 Model Information:

 Serial Number: C0****MA4

 Manufacturer: EGOWAY

 Device Name: A1405

 Pack Lot Code: 3230

 PCB Lot Code: 3038

 Firmware Version: 2d30

 Hardware Revision: 352d

 Cell Revision: 3239

 Charge Information:

 Charge Remaining (mAh): 5084

 Fully Charged: No

 Charging: Yes

 Full Charge Capacity (mAh): 6529

 Health Information:

 Cycle Count: 382

 Condition: Normal

 Battery Installed: Yes

 Amperage (mA): 235

 Voltage (mV): 7830

[Personal Information Edited by Moderator]