Have your WordPress theme/template options reset after you’ve migrated from one domain to another? All you may need is to export the data accordingly.
Export the old website's theme options before migrating
If you’ve migrated a website from one domain to another, you must export your WordPress theme’s options before migrating to your new domain.
Almost any good custom theme will include this option under its theme settings, therefore, look for an export/import option.
For developers who use a development server, you could still easily go back to the development website in order to export this. However, a big problem occurs when you don’t have access to the old website in order to generate this export file, as the data is often not saved directly into the database backup, unfortunately.