Large chunk of runs missed

I have a chunk of runs missing between November 19th and January 19th. I’m missing about 40 runs.

I know there is a section to add link by link to put these in the queue, should I do that for all of these? Or is there a way I can send over an Excel file somehow?

Are linked to e.g. Strava? I never had this myself, but I thought that ‘sync now’ (in the top right menu) would sync your complete history, so it should fill in the missing runs.