Cubase 12 not connecting to NI Komplete 13

Hi. I’ve been using Native Instrument Komplete 13 with Cubase 12 (OS Big Sur) for a few months. Up until now, occasionally when opening a project the NI instruments and plugins would not connect, but when I reopened the project or restarted Cubase they were there. Now there are not connecting at all.
Anyone able to help…?
Thanks very much. :slight_smile: