Model Pixma MG3500 suddenly stopped printing double sided

[Umfriend]

I was happily using this printer to print double sided on Friday. I have gone to print the same document, with the same settings, today and it will not print duplex. It draws the paper in as though it is going to, but then immediately spits it out blank. Have checked all the relevant printer settings and everything appears to be okay. This is really URGENT as I am in the middle of a commission and need to be able to print duplex. Any help gratefully received. 

[Stephen]

Hello!

I’m sorry to hear that you’re having trouble with your printer. To help the community assist you better, we need a bit more information:

- What is the exact model of your printer? (It can usually be found on the top or front of the unit.) MG3500 is the series, we need to know which one you're using.
- Are you seeing any error messages?
- Which version of Windows or macOS are you using?
- How do you connect to your printer: via USB or Wi-Fi?
- Have you installed the current software and drivers from https://canon.us/setup 

Any additional details you provide will help the community better understand your issue.

If you are in the United States and need urgent support, please click HERE to visit your My Canon Account for personalized support options.

If you are outside the USA, please click HERE to find support options for your country.

Thank you, and have a great day!