We had a Fire 7 kids for 1 yr and 8 months when the charging port stopped working. We traded it in using the Amazon Trade in Program and purchase this "All-New Fire 7". We set it up, but when I tried to add the microSD card to expand the memory, the microSD wouldn't "lock-in". I reviewed a troubleshooting video and it confirmed that I was inserting it in the correct orientation. (Also, when I tried to insert it backwards, it wouldn't even fit).
Just in case it was the microSD card I bought a BRAND NEW microSD card from Amazon "Made for Amazon" SanDisk 128 GB micro SD Memory Card for Fire Tablets and Fire TV". This brand new card wouldn't dock either.
I tried to the two microSD cards on my cell phone and they both "locked in".
So I contacted Amazon customer service to exchange the tablet. They responded relatively quickly and said that all Kindle exchanges must go through this "live" customer service process. I opted for the Chat feature instead of the live conversation. This was a nightmare.
Vivek, would take several minutes to reply to each to entry and he would ask me what I had just describe. Even prompting me to buy another microSD card even though I just told him I bought one. After 30 minutes, Vivek issued me a $20 credit to buy another microSD card!!!! How many microSD cards do I need to purchase and try? 3,4,5,10, before they will acknowledge that the Device's microSD card is DEFECTIVE?