Windows 10 in domain connects but fails to manually reconnect

[Alan Buxey]

without further details I'd say you checked the 'do not prompt' for
certificate..so it was connected but wont reconnect because its not
happy about the CA or RADIUS cert.
just ensure you've imported the CA used for the RADIUS server into the
correct root authority store so that the client is happy with the
server cert.
you really SHOULD have all those things (CommonName filled and CA
selected etc) - if doing a windows domain this is VERY easy with a GPO
that can be just pushed to
all Windows clients in the domain.

alan