Please confirm the cards you are using are full size and not micro with adapter?
You said you've tried several.
Next, please reset your camera to default settings. Now remove any accessories and the lens. Insert the card and power on. Open the menu and see if you can format the card?
If you cannot, remove the card and inspect the card slot for dust, dirt or bent contacts.
If the above does not help, your body will require service.
You can try Canon or midwestcamera dot com.
You have tried other cards without a satisfactory result.
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First try formatting the SD card in a Windows computer (not a Mac) and see if that makes a difference. Always use full sized SD cards, never, never micro-SD.
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