Hello and thank you for trying my puzzle and thank you for your kind feedback! I'm happy someone enjoys my game!
The last level should not be very difficult once you figure out the trick you need to execute. Think about how to 1) clear the 2 bottom tiles (the ones above the spikes) and 2) how to reach the right side of the level with the iron. The answer to both of these questions might be one and the same.
There should be a "Continue" option that loads the game from your last checkpoint (unless you played it before it was updated a several days ago)