I am the technical lead of my team and have joined that team a couple of months ago. Most members were there before I was. It took me a couple of weeks to earn the trust of my team but I was helped by the management and even upper management, and I now feel like I have achieved that. I, however, have issues in dealing with the most junior member of the team.
Whenever they ask me for help, I immediately make myself available (or make sure I become available ASAP if otherwise engaged with a discussion with someone else) and do my best to help. Very often, it's about small problems but every single time I face an intense resistance in whatever I suggest. Here is an example of what I mean:
Junior: Hey can you help, I can't synchronize the sources.
Me: Sure. What is the error you are getting?
Junior: Well, I'm trying to download the source from here to do this and that, and next I want to do this.
Me: Yes, makes sense. What is the error?
Junior: pissed for some reason, they shows me the error...
Me: Oh okay, yeah... this program can't deal with the passphrase on your private key. It's annoying and a security problem, but you'll have to remove it. Is there a particular reason why you generated a private key with a passphrase?
Junior: You can't have a key without a passphrase.
Me: Sure you can. I don't have a passphrase on my private key.
Junior: No. You can't have a private key without a passphrase. It's not possible.
Me: Well... You can. Let me show you.
Junior: No I don't want to regenerate a private key.
Me: You don't have to. You can just remove the passphrase and keep the private key you already have.
Junior: No. I'll find another solution.
Obviously, you can tell they weren't satisfied with my solution and while I indeed admit that it's a security problem when you have to get rid of your passphrase, it's something everybody did on the team, and it's just one of those corporate quirks you have to live with in that particular case.
I wouldn't mind if somebody found a solution actually, quite the opposite. But the problem is they has now been blocked for days and is still refusing the known solution - or workaround, depending on you see it. As a result, it's pretty much impossible to put them on any critical task, because there is no telling how long they are going to get stuck in such already solved-problems. This is all the more frustrating, because I actually think they are quite skilled for a junior developer and has shown that in many tasks.
Things are like that every time and only get worse when it's about a code review: no matter how diplomatically I type my comments ("I'm not sure to understand why we need ...", "I would avoid ... because of. What do you think?", ...), they are systematically received with refusal and no explanation. I am actually in a position where I could force them to do things my way or refuse a commit that doesn't do things my way, but I've never wanted to do this. I believe in convincing people with facts and numbers, not with titles and responsibilities.
I am at loss figuring out what to do here. I am usually pretty good with people and in 10 years I've never had a case like this. I went to our manager (we share a manager) about it, and he confessed that the other day they told him something like: "I'm very good at psychology and I think this person (me) has a narcissistic behavior and will ultimately destroy the team".
I have all the support of my manager but I can't say that didn't hurt and frankly, I don't understand any of it. I never once imposed anything and if anything, I am very open to new ways, discussion debate, and never once hesitated to say "sorry" or "I was wrong, my bad". I never done anything wrong - that I know about - to that person.
How can I deal with this situation? I can't refuse interactions with them (because I would be accused of favoritism with the other members) and every time they still ask for help, they react badly. It feels like I can't win.