Backup contacts to move to marketing platform

Hello all,
I have around 2,000 people in my Sylius system, this was from a Music festival we did this year, all GDPR compliant I need to backup all the contacts and contact mobile numbers to put into a new marketing platform.

How do i do a backup of everyone?
thank you

Hello @bashy2002, I assume you’ve already received some help on our Slack’s #support channel. Welcome to the community!