As a guess you have more mirrored datasets then expected. I have seen User get mirrored for example.
What does this show on the primary?
d ^MIRROR -> 1) Mirror Status -> 1) List mirrored databases

If both TESTTC01 and TESTTC02 existed before starting, your refresh process is also overly complicated.
You should be able to shutdown TESTTC01 & TESTTC02, copy the file from TESTTC01 to TESTTC02, start TESTTC02 and do a Activating and Catching Up Mirrored Databases. If you have a backup or snap of the file you don't even need to shutdown TESTTC01.