Filling layer error message
Adobe Photoshop 2018 CC. I use altgr+del button-command to place a large picture into a a small frame. When I try to fill the masked layer, the following message is recieved: "It can't be filled because of antecedent (history under) condition does not contains proper layer". My programme and computer is new, I do the whole action-process according to studied. In my case any button combination works to give command: alt+ altgr+del, altgr+backspace and others too.
please help
