Photos application stuck at "Updating..." and won't show any photos from iCloud Photo Library

Hi.

Yesterday I bought 50GB of iCloud storage and enabled iCloud Photo Library from MacBook. Before enabling iCloud Photo Library, I deleted all my photos from my iPhone because I only save a little part of my Photo Library due to storage issues. 

After uploading all of my nearly 6.5K photos and videos (.photolibrary file is 9GB) to iCloud from my Mac, I enabled iCloud Photo Library on my iPhone. After a short period of time, my iPhone downloaded like 3k of my photos then stop. There was like 4K missing photos but it says "Updating for X photos..." text under saved images text. It didn't move even a little bit after a full day. 

I thought it might be stuck so I disabled iCloud Photo Library from settings and it removed photos from my device. After a quick restart, I enabled iCloud Photo Library but now it just says "Updating..." when I open the Photos app. I tried disabling and enabling iCloud Photo Library back, logged out/in, restarted my device, but there is no use after several hours.

I can see my photos on iCloud.com and my MacBook's Photos app, they are synchronizing without any problem.

Also searched on Apple forums and everything but there is nothing else they suggest I didn't try already.

I'm open to any advice.