Problems after Multisite conversion

We are using Matomo WordPress Plugin on our site. We converted it to a multsite setup to add a new subpath “sub-site”. Matomo is not network enabled – it’s only enabled on the (existing, converted) main site.

We had a manual tracking code with _paq.push([‘setSiteId’, ‘2’]);

This now changed to _paq.push([‘setSiteId’, ‘1’]);

Is there any way to migrate / merge this so we see continuous statistics / graphs?
What’s the best way to convert an existing site to multisite – any experiences / know issues (I couldn’t find any documentation / issues about this topic)

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