key is created on openkeychain but can not be selected.
On the removed image of your posting it can be seen that you enabled PGP support, but you did not select a key. But you did select it in the meantime but still shows the init error on compose?
i creating a key on openkeychain for my email but can’t select a key on k9 settings encrypted mode because not working, if i touch this option nothing happen. and i have remove the first screenshot because can’t upload more than one.