Can't get magicians robes to work. help pls

[That1BIGDude]

For the life of me I can't figure out how to get magicians robe to work. I summon it face up and then wait for my opponents turn and I don't get a prompt to summon Dark Magician. I keep it in my hands and still don't get the prompt what am I missing does Dark Magician have to be in my hand is the card broken am I just being stupid. Any help would be appreciated.

"During your opponent's turn: You can discard 1 Spell/Trap Card, Special Summon 1 "Dark Magician" from your Deck (this is a Quick Effect). During your opponent's turn, if you activate a Spell/Trap Card or effect while this card is in your Graveyard (except during the Damage Step): You can Special Summon this card, but banish it when it leaves the field. You can only use each effect of "Magician's Robe" once per turn."

[This is a house]

You say you're keeping a card in your hand. Unless that card a spell or trap card you're doing something wrong.

[Ichmag 🔑🌙]

Make sure your prompt up things are fine? You can change the settings in controls, I think.
Also you need a black magician in your deck, it wont work if you have your only magicians in your hand

[That1BIGDude]

i was a dumbass and forgot to add him to my deck

[Ichmag 🔑🌙]

lmao