Product archives empty & products seem unvisible

We are currently working on launching our website. Unfortunately, we can no longer see the products in the product archives, nor can the products be found using the search function. However, the products themselves (especially the demo products from the theme) are all still there and activated.
Unfortunately, I can’t say exactly when the products became “invisible.”
I’m a little at a loss as to what we should do next.
We have already tried the following:
Ran the WordPress repair tool (clear transients, recount terms, regenerate product lookup tables, rebuild product attributes lookup table
Deactivated the Woodmart theme and switched to the default theme.
Checked whether products reappear when
– B2BKing Core + Pro is deactivated → Test.
– Deactivate Polylang for WooCommerce (leave Polylang Pro on) → Test.
– Deactivated Relevanssi → Tested the search (search only, not categories).
– Switched to the default theme (Twenty Twenty-Five) → Tested.
I suspect it’s not Woodmart’s fault – but at the moment, that would be the first place to start.