Deep Q Network gives same Q values and doesn't improve
I can see you are using "plain" deepQ, consider using double deep Q or duelling, but go first on your current implementation.

First of all, most of the times the problem is a bug, can you provide the history of the scores?. It is important to understand if the agent is learning or the best solution it can find is killing itself to minimize loses.

As per your hyperparameters, I will suggest two increase gamma first and decay epsilon slower.

Another tweak will be your alpha, reduce it a bit, seems too high.

Anyway, I need more details to help you, for example, Are you reading the screen ?, if so, did you reduce the image to something manageable?
Can you provide the full code?