Hello there, @asti-liebrecht.
Once your client's QuickBooks Online account is deactivated, you're given a year of read-only access to get all the data you need from your company. Just login to your client's account and export their reports and lists. I can guide you on how to do it.
You can read through this article the step-by-step instructions: Export reports, lists, and other data from QuickBooks Online.
Also, I'm adding these articles to help you manage your clients' account:
Always feel free to leave a post below if you have other questions about managing your QuickBooks account. I'm always here to help.
You have clicked a link to a site outside of the QuickBooks or ProFile Communities. By clicking "Continue", you will leave the community and be taken to that site instead.
For more information visit our Security Center or to report suspicious websites you can contact us here