weird hydro readings

so i got a american premium lager kit fermenting at 10 celcius with 2 smack packs yeast 2007, and 1 cup extra dme in it, cold pitched and it's sat for 12 days. OG 1.50. 3days ago 1.20 today it was 1.17 then i went upstairs to do some beer math 10 mins later retested for kicks and got solid 1.20. my numbers are true i really looked close and a couple of times each. am i done or should i keep on truckn in the primary.

and what if my Attenuation was l0w like 60% what can i do if anything at all?

if anyone has any imput it would be appreated

I just looked through my log and seen my OG was 1.056 and after week 1 it was 1.030 and at week 2 it was 1.022. At that point I racked to secondary to get in the lagering frigo. everything tasted fine after 6 months at 0c

Did you shake the samples for 30-40 seconds to de-gas them?

Yea, spin the hydro several times, then let it warm to room to 15 C.

Try another hydro.

Maybe your attenuation is not good because of high mash temp.