I lost my progress in my world when I transferred it to my new phone.

I bought a new phone after years, and I see that the file transfer method has changed; it no longer works the way it used to. I couldn't simply copy and paste the world folder into the "worlds" directory. I tried various apps for this, but they didn't work. I then tried compressing the world folder and renaming it to `.mcworld`. However, when I enter the world, it’s as if I’m starting for the first time—even though the displayed file size before entering shows the correct size (over 200 MB).

I tried another method using a resource pack to compress the file from within the game. When I transferred it to my new phone, I found my inventory items intact, but the world itself was essentially reset; I only found a small part of a mob trap and a village I had previously looted, while the rest of the world was brand new.

I tried transferring the world file using a computer, but the same thing happened: I couldn't move it. When I tried to paste it, the process would start as if it were working, but then it would simply vanish, as if I had done nothing at all.

I tried other apps and even used Shizuku (with root access), but the result was the same—I still couldn't paste the world into the "worlds" folder.