Does the LG K20V not have an NFC reader integrated? If not, then the ACR122U won’t work correctly with TagInfo because it requires different drivers and the command set is different than the native NFC radio… usually.
Basically what could have happened is that the “format” that was done inadvertently modified the configuration bytes in pages E1-E6… which are the last few pages of the NTAG216 chip. That position means that many software packages that incorrectly identify the NTAG216 may just attempt to consider those pages as “user memory” and just write whatever data they want to those pages. If that happens, then the possibility of permanently locking your tag, password protecting it against writes or even reads, or locking the configuration pages forever are all possibilities.
To get a sense of what’s going on, you’ll need to find a phone that has a built-in NFC reader, or a software package that can use the ACR122U to output all page read attempts and the results.