"I haven't seen you in a long time" should be accepted. Reported.
UK : not...for a long time
US : not...in a long time
This is where indicating where something has not happened in/for a long time (as distinguished from indicating that some action was or will be of long duration e.g. I'll be there for a long time).
The Ukrainian speaker should keep the grammatical gender congruent to his/her physical gender. I had to listen to this five times to confirm the female speaker was actually saying "Бачив".
There's probably a shortage of contributors with the enthusiasm for all the necessary hard work, unpaid. It's a popular business model: get a bunch of people to make me rich at their expense, then call myself an entrepreneur.
Why not past simple .. or does the word давно give the situation of a time frame and that's why present perfect.. then why not past perfect