Sorry to hear that. It’s just Random. I once went 3 weeks without one. Then all of a sudden had 2 in 4 days.
I did not miss an epic hero call and even called elements and luckily I do all the daily missions and when I build up 300 I get only 3 * me for a shame. Other players only 4 * 5 * heroes take
I like the sound of that, quite musical in English, seriously.