Android NFCA issues

Question

I have writted some data to NFC tag sucessfully. Now I would like to read all the blocks for double check. My codes looks like this and got TAG was lost exception:

byte[] UIDFrame = new byte[] { (byte) 0x26, (byte) 0x01, (byte) 0x00 };
try {
    NfcA nfcvTag = NfcA.get(myTag);
    nfcvTag.close();
    nfcvTag.connect();
    response = nfcvTag.transceive(UIDFrame);
    ...
}

Someone said IsoDep can fix this issue, but if I rewrote the code to

IsoDep aaa = IsoDep.get(myTag);

then I found aaa is null.

Can anyone help me to fix it? Thanks so much