On the nationwide online banking I can only seem to transfer money from my flex account to my cash builders account online, i can’t seem to move money form my cash builders to my flexi account.
Is that the same for everyone, do i have to ting up or go in store to do that?
Thanx in advance for answers.

Yes, it’s the same for everyone. The Cashbuilder is a passbook account, so withdrawals can only be made from them within the branch.
You could open e-Savings accounts through Nationwide’s online banking, then close the Cashbuilder accounts and transfer the money into the new e-Savings accounts. Once you have done that you will be able to transfer money in both directions, online.
You could also have an e-ISA, if you wish. This operates in the same way as e-Savings, but the interest will not be taxable.
nation wide is on your side