Lagging issue in my game

Question

I created a game called Buildy Blocks that resembles a 2D Minecraft or Terraria, but with touch controls. I'm still working on it, but I've found that the frame rate starts to drop rapidly after a few seconds of the program running. Why is my game doing this and what can I do to keep it at a constant 60 fps?
https://code.sololearn.com/WsGZOujUiBN4/?ref=app

Answer 1

I am not seeing any problem, maybe your device or your version is too low or something. Great game though! I had it running for about 230 seconds.

Answer 2

How long did you have the game running for?