Not soaking the beans before cooking them could be the culprit. Refer to the instructions for loading the Pressure Cooker on page 5 of your Pressure Cooker User Guide for specific tips related to dried beans and legumes. If you already soaked the beans, you may simply need to cook the beans a bit longer. Place the pressure cooker base on the cook top (with the lid removed) and simmer the beans until tender. Add water, if needed.
I used my pressure cooker to cook dried beans. When I opened the pressure cooker, they were not soft enough for serving. What should I do?