I decrypted my external hard drive and now it's locked and unmounted?

I am just having a multitude of issues here. After trying so many things I have found myself in a deeper hole.

I am using an external hard drive, it is a Seagate Backup Plus 1TB external hard drive. It is formatted and partitioned, I did this using the steps provided to me from Seagate's website when I first got it.

I got into the hole I'm in right now because I was having issues backing up my photos from Lyve to my external drive. I think the reason why they wouldn't back up was because my drive was offline in the 'Status' section in Lyve, despite the fact that Disk Utility said the Disk Status was online. I researched this and discovered that this may happen if either a.) the storage is full, or b.) the wifi connection is bad or a connection is not availble. When I opened my Seagate Dashboard I discovered that my drive was full, so I figured that was the reason. This made no sense to me because there was no way I had somehow already filled up 1TB, I had only backed up once and it's brand new. Nonetheless, I deleted a ton of photos that I had put into 'Lyve Import' and then cleared the trash. (I must've accidentally imported them multiple times, so the photos doubled quite a few times or something because altogether they're 50GB, not 1TB...) That appeared to be the source because then my drive had 938 GB free!... But my drive still appeared offline.

So I refreshed, restarted, unplugged and replugged, turned Wi-Fi off and on again for Seagate, Lyve, and my computer. But my drive was still offline even though Disk Utility still said it was online.

Now, I'm still in the process of discovering why it is that my Drive was appearing offline in Lyve when I've used different Wi-Fi connections in different locations and they all worked fine, and I have plenty of storage. One reason I suspect is that the partition on my drive still has all of the photos from Lyve Import copied that I had deleted, because there is almost no storage on that partition somehow. As you can see in the second photo, the partition says it only has 16 MB available, and I've somehow used 999 GB. If it's the same case as before, I don't know how to access that partition and delete them. Is it a copy of all of those Lyve Import photos? Nonetheless...

NOW, currently the main problem that is preventing me from continuing investigating the previous issue is: I had encrypted my external hard drive some time ago. After getting annoyed with having to enter a long password so many times because of all of the restarting and such to fix the 'offline' problem, I decrypted this hard drive by right clicking it in Finder and clicking Decrypt. I entered the password to do this, and it decrypted as far as I know because the password was accepted. But now, my Drive says it is locked, and unmounted? What? It is greyed out in the left sidebar of Disk Utility. It also doesn't appear as a plugged in device in Finder. It's like it's not even there anymore, but I can still access Lyve. From what I understood, encrypting my drive would protect its' contents with a password. Decrypting it would mean that I would no longer have to type in a password to access it? Seriously worried that I screwed up something because I didn't understand what the consequences would be here. Also, why is my drive not appearing when the partition says the Disk Status is online?

I included photos of the information of both the drive and the partition and what they currently look like in Disk Utility. Previously, from what I can recall, in the information section of my Drive it had about 948 GB available, was mounted, and it said it was an Encrypted Logical Partition, if that's of any use. It's not displaying this information now because it is locked, correct? I didn't erase anything?

As you can tell, I did not know what I was even doing in the first place- and now I am stumped. Please bear with me on this because all of this formatting and partitioning and mounting and the like is confusing me, the only knowledge I had was from the steps provided in forums or on Seagate's and Lyve's directions on their website. I don't really get what it means anyway- I wasn't trying to just screw around with things... Any help would be IMMENSELY appreciated.

^ Note that this is what my Finder looks like now despite the fact that my external drive is plugged in. It always used to show the Drive right in the middle of 'FAVORITES' and 'TAGS' as a device that is currently plugged in, with the option to view its' contents or eject it.