Linking recently viewed products doesn’t work

Hi, I am using your plugin, and I think it is great. But unfortunately it causes an error on my site. After enabling this plugin. Links to recently viewed products stop working. The links are getting a null redirect.

When I click on the link instead of opening normally, a 404 page opens, and the link in the top bar of the browser looks like this.

https://unisynk.se/products/null

Please help.

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