Hmmm..my inbox is at 14/400, so nowhere near full. After lots of restarts, the goodies still don't show up. Such a pity.
Have you tried closing & reopening the game? If the issue persists, please open a support ticket through the in game option or here: https://mobile-support.plarium.com/hc/en-us/requests/new?ticket_form_id=360000007492&_gl=1*z1rke6*_ga*b2lkODU1MTEwMTA2OS4xNjYxODI2ODE1*_ga_5FNDF9DMY8*MTY3MTkxMzAzOC40MjcuMS4xNjcxOTE0Nzk2LjYwLjAuMA..
Thank you for the advice, I submitted 3 tickets, one for each account. Third day now of playing on PC platform and haven't got the popup and I have to tell you I'm playing lots of hours. I don't know if it's really a bug or not, but would like to get the gifts until the period ends, would help me a lot. :(