NUX mini studio not detected during firmware update

 Recently bought from Amazon this NUX mini studio IR loader and when I tried it using the earphones out. It did work. It was on red and according to the manual it's guitar amp/cab sim. Then when I tried holding down the footswitch for 2 seconds or more to change it to bass sim, it kept flashing and Im not able to turn the flashing off unless I hold down the footswitch again for more than 2 seconds. 

I don't know if it meant to do this way. So I refer back on the manual that came with it but there's not much written on it. I searched online and found nothing on forums about this problem. Then when I went to NUX website, there's more in there like what are the amp/cab sim for electric guitar, bass and acoustic guitar and to activate it by holding the footswitch for 2 seconds which I knew because I've watched videos on YouTube. 

That's when I downloaded the firmware update as well as the MiniStudio software for my MacBook Air. Then I tried connecting using micro USB. But the unit was not detected. So I can't install update or even use the computer to tweak the pedal. 

I decided to use my laptop, windows 10 and downloaded both softwares. Installed and connect the pedal. Still not detected. I've used 4-5 different micro USBs that I use for my Guitar Wireless System, mini table lamp and I can't remember what are the other micro USBs. But it didn't work.

I then contacted Amazon to return the unit for exchange. I was offered a customer assistant if they can help me solve the problem but all I got was just giving me information on the unit i.e. 9v power supply centre negative polarity, etc. More like what I've already done. 

Then another specialised customer assistant helped but more on to process the exchange or refund. When they check they could not do exchange only refund. So I decided to return the unit and asked for a refund. 

Has anyone experienced this with their NUX mini studio IR loader? Kindly leave on the comment section if you managed to sort the problem or even just the experience. May be there's a solution or there's something that I missed. Thank you!