I just had a thought. If you still have the iPhone 7 you could try backing up both phones following the instructions HERE Then restore from the 7 to the X again. You would lose anything you've added to the X since and may want to revert, but it may be worth trying. If you back up the X you can always revert. Level progress…
In that case it would indicate that, as @Sukanta_Biswas says, you have somehow been removed from the group of players who get this bonus for now. I'm wondering if the episode trophies may be stored on the device, along with the boosters, in which case they will not have transferred, but why it is not giving you new episode…
@Elsa Indeed 2 of them were saying exactly the same thing ;-) I haven't been keeping up with your stories lately and must go back! Please tag me when the Easter story is up.
@Elsa I think the idea is to find the answer for yourself 1st, then read everyone else's ;) You're not the only one though. Did you notice any similarities whilst you were looking?
Hi @Saraswat94 and welcome to the community. You could try contacting support, but in reality they are unlikely to be able to help as they can't be responsible for the performance of the game on your device. Always make sure that your device has the required/recommended memory available for any apps you use before playing.