Acer fungus

Jenny341

This soft brown fungus type growth has appeared on the bark of my Acer. I don’t know what it is and how to deal with it. It’s a darkish brown inside and out and is soft and floppy. The tree is about 14 years old and appears healthy with new buds showing on all branches. We live on Romney Marsh and it has been pretty damp the last couple of months. I haven’t been able to identify it from photos online - can anyone help please?