Welcome to the Community, @Dedar12
Do you have any other plans on your account that aren't unlimited, or is it just the three SIMs you've mentioned above?
You do have a 100GB gifting limit on unlimited plans, so if you've previously gifted data to another number on the same account, this will show a decrease in the giftable allowance.
It's also worth checking the plan name for each number on your account in the EE app, or you can also try texting AL to 150 which should confirm any allowances.
Peter
