Moral dilemma

In honor of Rabbi Dr. Michael Avraham
Peace and blessings!
A small dilemma recently occurred to me, and I would like to share it with you:
I'm a yeshiva student, and about a month ago I went out to do some business in the city (during break), and I came across a disabled elderly man with one amputated leg, who asked me to carry him to the nearest square (it's not that far).
Of course I said yes (for moral reasons)! While calculating my time, and aware that I would be late for the next lesson. I began to carry it with great difficulty (an adult weighing at least 90 kg on difficult climbs). But I had the satisfaction of doing the right thing and helping and being kind to a person in need.
But things started to get complicated… When we reached the square, the same man told me "to the grocery store" and from the grocery store it extended to "to the intersection", etc., etc. – it was a whole tour of the city, and it took a lot of strength out of me (and a streaky lesson).
It really annoyed me that the person supposedly lied to me in the first place, and didn't tell the truth that he wanted me to carry him for a long time (and I assume it was a trip for him, and not really a concrete need for anything in particular). I got frustrated and went back to that adult – and that's how the day ended.
About two months later, at exactly the same time, I was passing through the same area, and I was with a friend. And here we meet the same old man who was being carried by someone else, and that someone left him. My friend thought he was a beggar and waved him off, but I already understood what he was talking about, and when he asked me and asked as usual "to the square", then my friend agreed willingly, while I pondered the matter.
From there, we started carrying him "to the square," and when I told my friends the problem they were now facing (and this time there was also an important test in the yeshiva), and also that it was probably his travel time that he was asking all sorts of people to carry him, and the fact that he was "lying" "to the square" and that it was actually a long and tiring walk, then we fought to make sure it really would be "to the square."
The question: Is this a morally correct step? After all, this is an elderly and disabled person whom I have a moral obligation to help! Or is the time wasted a valid consideration that could tip the scales in my favor (and there is no moral problem)? And does the fact that he lied, the anger about it, affect anything here?
I share with you, and I would like to hear your opinion on the matter (and if you could expand on this in a reasoned manner, I would be very grateful).
Thank you very much.