Techbox self collection address same as the infamous JTBC, so either they are affiliated or one and same seller. I would stop short at calling the seller scam but they are a pain in the rear to deal with.
My personal exp ordering xiaomi mi 9t from JTBC on qoo10 last year. I left a message on qoo10 asking them whether they have ready stock for self collection prior to ordering. They replied yes but best to call their office to confirm(wtf?). Called up their office and was told the person in charge of handling qoo10 orders away on leave so need to wait for them to call me back(double wtf).
After a few days, received call from them asking me for my order number and they told me to stay on the line. After on hold for around 5 mins, they ended the phone call on their end without saying anything. I got so fed up i cancelled the order on qoo10 and ordered from vimobile instead which i even managed to self collect from their shop at orchard on the same day.
Eventually JTBC sent me a message on qoo10 some 2 weeks later saying my order is ready for collection when i already cancelled and received my refund. They really super cork up. I suspect they got no ready stock in hand to fulfill orders. Probably their MO is to consolidate a bunch of orders then one time take stock from supplier.