Azure powerbi embedded capacity pricing Not accurate!

I'm concerned about the billing process for powerbi embedded service. I don't know how it takes hourly bases, because I activated the service at Apr8 at 12-1 pm. After the end of the day means approx(11-12hrs) the bill should generate for that day. But in the invoice details, it shows 17.53hrs and for Apr9 end of the day, it shows 24hrs like that. And I suspended the service on Apr11 at 12-1 pm for that it shows 500rs as usage for powebi service. I really didn't know what's going on! I attached the invoice provided by azure, please answer me, if you have any idea what's really going on!