how do i upgrade to unlimited data onto my current plan?

Hi there ​@Stephanie Share 

Shh, actually you can. They have a dedicated sales number 0207 139 1397. They should be able to tweak the account (number works during normal office hours).

Or this

• What is a Plan Change? F.A.Q.

But note

You can change plans after 30 days. However, if you’re a Pay Monthly customer, you cannot change to a plan that is cheaper than your original plan, as you still have to pay off the remaining balance for your phone. You can swap to a plan that includes more data at a higher cost – and if it doesn’t work out for you, you can change back to your original plan (as long as it is still available).

You’ll also have to meet all of the usual eligibility criteria, such as:

• You’ve been with us for more than 30 days.
• You haven’t changed plans within the last 31 days.
• You have an active direct debit with us.
• You don’t have a disconnection request pending.