Plugin not active across multisite network

Hello,

I’ve just installed the plugin Stock Sync, which is designed to sync stock across the multisite network. I’ve network activated it but it is only showing up on my primary site. I don’t think it has anything to do with the plugin itself because I activated another plugin earlier today (now deactivated) which also didn’t show up on my second site.

I’ve recently transferred web hosts (completed today) and am awaiting the nameservers to be changed in case that might make a difference although I can’t see why it would.

Please can you help. Thank you.

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