In the form load event of tt_form, you're setting all the textboxes to a zero length string (= ""). That's blanking out the first record in the table each time the form loads. Then you type in new data and the first record is replaced by that info. Take all that code out.
If you only want to be able to enter new data on the from and not view pre-existing data, open the form in data-entry mode.
And you should add "Option Explicit" after "Option Comapre Database" in all your code. It will show that you have several undefined variables in your code that need to be fixed.
Option Compare Database
Private Sub btn_TT_Click()
DoCmd.OpenForm "TT Form", , , , acFormAdd
DoCmd.Close acForm, Me.Name