i have .tar.gz database dump file, created with dokku mongodb:dump database -tar (dokku mongodb plugin)

now i want to restore it to db with different name (newdb). running dokku mongodb:restore newdb dump.tar.gz gives The .tar.gz-file didn't contain a database-dump for newdb.

i've untared archive, and renamed the folder to match new db name (newdb). after running sudo dokku mongodb:restore newdb newdb it says Successfully restored database newdb from newdb. I can see in mongo console that records are present, but from the browser it looks like db is still empty;

How do I restore it properly?