I bought my GPS tracker from GPS Tracker Centre on AliExpress, and everything was fine, until I wanted to change a SIM card - the card holder just fell off of the tracker PCB ...
Despite photos (including via a digital microscope) and a very polite request, the seller refused to send out a replacement board (I wasn't even asking for a complete device!) and also refused to cover the postage cost to return the defective board. I posted it anyway, as it was only £3.15 for a standard airmail.
However now, more than a month later, the seller just ignores my messages - no acknowledgement of receipt, nothing.
The rep name listed as Tina Zhang, although that's probably just a handle.
Just thought I share this with the forum.