Welcome to the forums, @hakanozkan123!
This is just an explanation for the behavior. There are some technical restrictions for an application on Glitch - disk storage limit, anonymous-expiration, RAM and request limitation, etc.
Projects have a limit of 200MB of disk space in the container. The contents of your project’s ‘/tmp’ directory currently don’t count towards that total, but those files are removed when the project restarts. By default your Node.js modules don’t count towards that total - there’s a separate 1GB limit for node modules. Plus, there’s an additional 512MB of assets storage space.
Learn more here and Happy Glitching!