post May patch mid game restart
At the beginning of game two after i played my first land Shelldock Isle and was resolving the Hideaway trigger the game startet again. My Opponent and i both got a new hand of seven cards.
Each turn after that the client went directly to the cleanup step and made us discard a card due to maximum hand size.
For this issue, please submit at: https://mtgo-support.wizards.com/hc/en-us/requests/new and select 'Reimbursement Request'.