Hi mgammal,
When Err70 happens on a camera it would freeze, so the two freezes without the error message could have still been related. The settings you listed are in line with what we would expect. Those settings shouldn't be causing the camera to freeze.
Typically Err70 is related to the camera being unable to write files to or read files from the memory card. I see you mentioned it was happening when you were focusing, but it would still be good to try loading different memory cards in the camera to see if the same thing happen.
If the issue continues the next step would be to attach a different lens on the camera and take some test shots to see if the same thing happens. That way it can be narrowed down to if the issue is being caused by the lens or the camera body. If the error is only coming up when your RF100-500mm lens is attached we would recommend sending the lens in for repair. If the error is coming up regardless of the lens attached and memory card used we would recommend sending the camera in for repair.
If you send the camera or lens in for repair make sure to include a copy of the proof of purchase in the box. The technician will need that to verify the warranty.
Canon U.S.A., Inc. has created a new online repair portal that allows you to set up service in a few simple steps. The repair portal gives you the ability to set up service for multiple pieces of equipment at once, and to receive a repair estimate in the majority of cases, depending on your model and issue. The portal also allows you to upload images or videos that will assist us in repairing your product. You can also select how you wish to be notified of the progress of your repair. The portal's service history section allows you to view all services that have been performed on any of your camera or video products since January 7, 2020.
Please follow the link below to access our online repair
https://mycanon.usa.canon.com/signin
Instructions for Accessing and Using the Online Repair Portal
You will need to access or create your My Canon Account.
If you already have a My Canon Account and your product is already registered, simply click on the “Get Repair Services” link on the left menu and follow the onscreen instructions to arrange for service for your product.
If you have a My Canon Account and your product is not registered, you must register your product first. Click on the “Get Repair Services” link on the left menu, then click on the “Register Product” link on the right. After your product is registered, click on the “Get Repair Service” link on the left menu and follow the onscreen instructions to arrange for service for your product.
If you do not have a My Canon Account, you will need to create one. After you create your account, click on the “Add Product” link to register your first product. After your product is registered, click on the “Get Repair Service” link on the left menu and follow the onscreen instructions to arrange for service for your product.
Once you have completed the repair request, you will have an opportunity to print a copy of the request for your records. This request form will also contain shipping instructions and an address label that you will attach to the outside of your shipping box when mailing your equipment for repair.
