@dzungpham0703
I buy them on Aliexpress:
https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20180706102504&SearchText=HTTM
If you apply hot air it is easy to take off the white "double sided tape" and the plastic.
I think I found the problem. I think it misbehaved because of an illegal character in the "HOSTNAME". Changed the hostname yesterday and It was still alive this morning even if I have not pinged it.
