Problem with uploading Minecraft worlds

Greetings. I recently encountered an issue when uploading Minecraft worlds from my device file folder into the game. I always used simple option to do it: in file folder I simply double pressed .mcworld file when game is running and the world would load into the game. But since yesterday, they aren't loading into the game when it's already open. I tried reinstalling Minecraft Bedrock several times. Can you help me out on this. I could also provide recording.