Sword of Spirit
Legend
Because the duration of Lightening Arrow is a concentration check with a duration up to one minute and includes any attack made during the spell's duration, our DM had no reason to say it couldn't work as long as the checks were made. That made things extremely fun.
Volley also modifies the attack action and is itself treated as one attack; not much different from the Volley found in the Pathfinder games.
"The next time you make a ranged weapon attack during the spell's duration..."
The spells that let you keep on doing damage (hex, hunter's mark, divine favor) say, "until the spell ends".
I'm sorry, but that just isn't a valid reading of the text. Your DM is house-ruling. There is nothing wrong with that, but if he wants to know how the rule is written to work, it's a single use during the spell's duration. (Which means you might as well stop concentrating on the spell immediately after, because it is useless for the remainder of its duration.)