Miles & More (Lufthansa, Austrian, Swiss, and other partners) - Combining MM Accounts, Deutsche Bank Anniversery Miles

I recently got a voucher for Miles from Deutsche Bank. The included letter stated that the voucher was honouring some Deutsche Bank anniverserry.

I did of course accept the Miles. However, DB opened a 2nd MM account in the process.

Is there any standard way to combine acconts, or do I just go back to MM and ask them?

I had the same when my mother applied to the M&M-Credit-Card.
They opened a new account and in the meantime some miles expired.

I called the hotline and everything was sorted out. As you normally (yes I know that some have more accounts...) have only one account, it is clear they merge them. In my mothers case even the expired miles were credited back.