Moving live site to staging site

All our sermon recordings are in a folder on our server & the entries Sermon Manager points to them.

I’ve moved our old website to a parked sub-domain, so that I can still access it. All the website links have been updated to the new site, but the Sermons are still linking to the old domain so don’t work.

Where do I access the database to change all references from ‘https://www.thurnbychurch.com’ to ‘https://oldsite.thurnbychurch.com’ please?

I’ve tried exporting, editing the xml & re-importing, but WordPress gives an error saying ther sermons already exist so won’t import the changes.

Do I need to wipe the database & import it again clean (with the alts already applied) or is there another way of doing it by simply editing the existing database.

Thanks.

The page I need help with: [log in to see the link]