Can you look at the "Detailed Tax Summary" and see what amounts are on Line 323 (Tuition & Education Amounts) and Line 435 (Total Payable)? If your "Tax Payable" has not been reduced to "zero", your tuition will be used by you and not available to transfer. (You can be in a refund position and still have "tax payable").
And please verify with us that you are transferring your 2017 tuition, as you cannot transfer tuition amounts which you have carried forward. Thanks.