How do I recover a PSB file? Shows only 1 layer when opened in photoshop while I had 90 layers?

[Salmanghani]

Hello, There! Help me out I'm in big trouble.
So, actually what happens is I was working on manipulation artwork for 2days and saved the file as a "PSB large document" as I was working on the project suddenly due to an unexpected system shutdown due to electricity fluctuation. When I opened the PSB file again after an hour. It's just showing only "1layer" while I have (90+ layers before).
The size of the PSB is 735MB but shows only one layer when opened.
How can I fix this issue and recover my layers back? This all happen due to an unexpected system shut down and the PSB files crashed.

Please help me out with how can I recover the file? I had spent quality time making it. Thank you!

[Michael Bullo]

Any chance you are working out of Dropbox or some other form of cloud storage where you can access earlier versions?

[Salmanghani]

Yes, I will be using Mega drive in the future to save my progress and upload the file there so that I have a backup option uploaded there, whenever I've any PSD crashed issue will download the earlier version file from there.

But what about now? I didn't upload any earlier version files to the cloud? Is it still possible to recover my crashed PSB file?

How can I refrain from this issue in the future so, that when photoshop suddenly shut down and I don't lose my file. This is frustrating as I've done much work on the file, I also enabled auto save in preference and set the time to 5mins so I get a backup option in case of sudden system shutdown. Thank you!