Your post is confusing. The usual definitive test
for Hepatitis B positive is the HBsAg test. If you test positive
for HBsAg then you are Hepatitis B positive.
In some rare cases, you may test HbsAg negative, but your viral load (hbvdna) is detected, then you have what is known as Occult Hepatitis B.
Most likely in your case, you tested hbvdna "negative" after being on Lamivudine, but you still tested HbsAg positive.