“Terrible attitude and seemingly quite incompetent”

These guys took over the management of my apartment building last year. Since the start I've been a proactive property owner, maintaining my property to a good standard and paying all my bills on time. Yesterday I had an enquiry about a possible leak from the apartment. As it was a Sunday and they were closed, I emailed them. Today at 2pm I still hadn't heard anything back despite the issue obviously being important so I called. They claimed not to have received the email and I had to explain two or three times when the email was sent and to which address. They just couldn't seem to wrap their head around this for some reason. Eventually I was transferred to a Mr James Coote who was responsible for the property so I set about asking him the questions I'd asked in the email. Immediately the guy became aggressive and confrontational, threatening me with having to gain entry into the apartment to fix a leak if there was one and having all associated costs sent to me. But I hadn't said I didn't want to fix the leak - I just wanted to know whether they had any options - like using the caretaker - to ensure there actually was a leak before I went ahead and paid £70+ for a plumber to come out which I don't think was an unreasonable request. I ended up hanging up on him because he clearly had no interest in working with me here to get this issue resolved. I wouldn't bother calling them for anything again, and they've lost my support with any issues they may face with the development or its occupants.