I have 2 characters that already pass through 5 days login and should have got gacha ticket. But it doesn't seem like there's any trace of the ticket.
I thought it would be delay for a while but it's 2 days later.
When i go inside nyankoropon, the spin button only show "insufficient tickets'.
Is it bug or something?

Did you check your System > Presents? If you did, I can't think anything else other than a possible game bug.