I believe that the cause of this issue is Nintendo's fault. Earlier this month, they have released the 12.0.3 system update, which causes some problems downloading different software (Including the Minecraft Updates!)
A few days ago, they recently provided another update, but that one too has problems.
Try to keep up with the updates, and see when the next one comes out. Then, see if the game opens again.
Kosta
IMPORTANT READ THIS:
I believe that the cause of this issue is Nintendo's fault. Earlier this month, they have released the 12.0.3 system update, which causes some problems downloading different software (Including the Minecraft Updates!)
A few days ago, they recently provided another update, but that one too has problems.
Try to keep up with the updates, and see when the next one comes out. Then, see if the game opens again.