matomo plugin ecommerce tracking

I recently switched from GA to the matomo plugin for wordpress and just found out that it doesn’t register any e-commerce events. For instance if a customer buys a product it isn’t shown as a conversion.
I read somewhere that I need to define goals first (is that correct?) – is there a documentation somewhere on how to achieve conversion tracking with the wordpress plugin?

I do have e-commerce activated under settings of course.

Help would be much appreciated, thanks in advance!

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