changed name and now all data invisible

changed name and now all data invisible

Dear Support,

I changed the name of the Superadmin including the contact email and now it seems all leads, contacts etc. are invisible (hope they are not gone...).
What can I do to let's say transfer the rights of the "old" (deleted) user to the "new" (existing) Superadmin?

I still have these "verification codes" and hope they can be of help.

Appreciate you help.

Kind regards