Are you using TagInfo app?
It absolutely should read your HID iClass SE Access card and your NExT (NFC) no problems.
If not, we need to look at your:
NExT placement
and
Your make and model of phone
check out this for known compatiblity
and / or research you phones make and model NFC antenna placement.
BRIEFLY let me know if you need more guidance)
Phone cover off
NFC on
Screen on
Open TagInfo app
Tap your access card on the back of your phone it should read easily
Clear the data
Now your NExT
Move phone slowly over implant area in different orientations.
Alternatively you can use your diagnostic tools you would have recieved with your NExT order (xField detector RFID diagnostic card)
You really only need the xField detector for this but Diagnostic card helpful also.
Find the brightest LED position and orientation(s) then try to scan your NExT again over that position in the same orientation.
That all being said… Can you confirm it is implanted and not still in the needle (people have tried before) 
