404 error on brand pages

Hi,
I installed the woocommerce perfect brands plugin last week and it worked beautifully. But today I looked and all the brand pages produce a 404 error. The main brands page works (https://www.chalkandmoss.com/brands/) but when you click on each brand, the page doesn’t work. The same happens if you access brand pages from the main menu – shop>brands

Please can you quickly help? I can’t leave it looking like this on the shop, but I need to keep the plugin active so you can see the error and help. I can’t think what might have changed to produce this error.

Thanks so much!

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