iPad keyboard only works sporadically

My iPad has he older folding at acted as a cover. After an update some time ago I started getting notices saying “accessory not supported”, and the keyboard only works sporadically. Also I have a Bose speaker which uses he lightning connector. It used to connect, but now I get the same error and it will not play. Any ideas as to what I can do?

[Re-Titled by Moderator]