Help with sim card

[Android Central Question]

They asked at Wal-Mart. Whats your carrier? I said what do mean i bought it on Amazon. So i looked through papers and the packing list says LG V20 and then in another column it said ATT not AT&T but i took for being AT&T phone. Anyway theres an att Verizon and some other one there all the same size sm med and lrg. The little one does but it doesn't seem stable? Help

 

[Laura Knotek]

The LG V20 uses a nano SIM.