If in RAW, you should be able to use Canon's free DDP (Digital Photo Professional) software or most photo editing programs to edit the files to regain the color. If you shot in JEPG, there isn't any way to regain the color.
If you did shoot Raw, you can try Canon DPP Express. It's in the Apple App Store for download to iPad or iPhone. I've never used it, so I'm not sure if it will remove the B/W filter, but it's worth a try IMHO.
I you captured the images in RAW, you'd have the original color images without an effects applied. If you captured only in JPEG though, you're out-of-luck. The only thing you could do is attempt to hand-color the photos in post-processing which would probably not be worth the effort, unless of course these were once-in-a-lifetime images.
For the latter, you can explore different techniques in Adobe Photoshop. There's a version of that app for iPads (though it may require newer iPad models).
12/05/2023: New firmware updates are available.
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.