Replace Text Using Replace Buton

In User Form i place one listbox1 in which you will get a data in column format, when you search by any criteria and when you click on data it display in respective text box (For Eg: First Name Data display in First Name Text Box, like this u will get.)
the real problem arise when i edit data and try to replace by clicking Replace Button :position data is not kept,are replaced data from the first position

So Please can any one do the correct code for me.

Waiting for reply,

qwzx