@v
1. Not enough followers
One of the people I talked to had 10 followers and was surprised they had no engagement.
You absolutely need to build a following. A good rule of thumb is that if you have 1k followers, then 100 may be online today, 50 may scroll enough to see your cast and 5 of them may like it.
If you don't have 1k followers, work on fixing that. Just posting casts won't get you more followers. You also need to reply or interact with others so they notice you and click follow.
It's important that these interactions are helpful to others. If you are simply trying to farm follows, people will notice and it will have the opposite effect.