Thanks for the query.
The urine pregnancy
test kit measures beta hCG
levels in the urine.
These levels will take some time to comeback to zero level after abortion
This time will usually depends on the gestational age
when the abortion occurred and the levels of beta hCG at that time.
Possibly that is responsible for your pregnancy test positivity.
So, if you are not having symptoms like pain abdomen, bleeding etc. no need to worry.