Updates does not synchronize with iTunes

Just wondering if it is happening to others too. Previously when I used to update apps on apple devices and synced with iTunes, the apps in library were being updated automatically and vice versa. I have noticed it is no longer happening and I am having to update apps individually on each and every single device separately. I have tried all possible trouble shooting including fresh iTunes install on fresh Windows Install and even fresh restore of IOS on all devices. What could be wrong??? It is costing **** lot of data and hassle to keep doing things individually. I use 4 apple devices and have iTunes on windows laptop.