Problem with Migrate - deleted my customized doctype

I need help when customized my doctype worked perfectly but when i migrate the customization it deletes
Peek%2017-12-2019%2009-34
Peek%2017-12-2019%2009-36

You need to export the fixtures after customization. If you do migration directly then migration will read old JSON file. And the customization gets deleted.

Command to export fixtures. (This will updated the JSON files with the latest changes)
bench export-fixtures

yes i do this and have the same problem