Don't panic there is nothing serious going on at all.
Buy a new SD card, depending on which boot loader you are allowed to use, with a boot loader equal to or lower than 5.5020 an SDHC no larger than 2GB, with a boot loader larger than or equal to 5.5025 SDHC up to 32GB.
But it can also just be that something is wrong with your navcore, if it is still the old navcore, you must first provide it with a patch before you can use another map.
I guess the last thing happened to you.
In the most hopeless case, send me your ttgo.bif file, then I create a file for you that should work immediately, all you have to do is update that bootloader to version 5.5128, the same one I have been using for years. Rider v2 and can process all maps of the world.
Be careful with that update, make sure the battery is fully charged, just to be sure, connect the Rider to the power supply, pick up that loader 5.5128 somewhere, if you can't find it, I will send you a link.
Format the new card fat32, put it in the Rider v2, reset and restart the device, a new ttgo.bif file will be written but you will not get further at that time.
Now take the SDHC card out and copy the loader 5.5128 on it, reset the rider again, insert the card and start.
Now very briefly a text will appear on your screen telling you that something is being installed, it will be gone before you know it and your Rider v2 will also be unusable if the power goes out at that moment, so again pay attention because that is the biggest mistake that you can make.
Tell me which map or maps you want on it, that's no problem.
Here somewhere my private email address must be roaming around I think, if the extension is xs4all.nl then it is the wrong one, in that case a PM is the most useful.
Good luck.
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