As being part of the MT in a very specialized area, I het a lot of questions every day, not only from my own team but also from others.
In cases these are recurring questions, I always remind them we have discussed it prior and what did they take away from those earlier questions. Then you often notice if someone does not understand the topic or is lacking confidence to continue further without having a reassuring answer.
In case it is the latter, I encourage them to find their own solution and only to check in with me if they want a second pair of eyes de on correspondence with clients.
However, I also regularly book a few hours with if I need to meet certain deadlines and I tell them I am not available then due to this or if they walk in at the office, they sometimes have to wait for a few minutes before I have handled something else. Then you often notice that they do know it but wanted reassurance.
In cases that the questions were not to be resolved by me, I consequently send them to IT te. It takes time but I hardly get any IT related questions, only to check if my system is not working properly also, so it is a general IT matter or not.
It takes time and it also pertains to giving boundaries to that person. If they come to your desk often, say that you are busy and can they gather all their questions and come back in x amount of time, so you can go over them together. I would also expect the colleague to be taking notes then btw