@Echel0n GrapheneOS updates don't remove any data. By not updating, you've been using an insecure device without basic privacy and security patches. You don't have ongoing bug fixes or support for the current GrapheneOS services. It's not expected for things to continue working properly if you're not staying relatively up-to-date.
GrapheneOS has a built-in backup system. If you had been updating, you would have major improvements which were made to backups in the past year. Since you aren't updating, you don't have the current capabilities of the backup system.
You're not using recent GrapheneOS and we can't provide support for using very outdated versions of the OS. If you want support then you're going to need to start staying at least relatively up-to-date.