I don't know where to start. Whether it is - That is an interesting moment to make a first ever forum post, or - You reached chapter 8 before you realised that Magic Residences cost diamonds? I won't go on about various sources of free diamonds and free Magic Residences because other people have already done that.
So curiosity got the better of me and I looked you up. Two cities started at the same time in about March 2018. You then seemed to stop playing in about August 2019 and have perhaps logged in very occasionally after that time, before starting to play the game again in April of this year. One city has never been in a Fellowship and the other has been in a few long enough to find out about Spire of Eternity and free magic buildings... No, I still haven't figured it out.