S6 edge battery drain on idle (android os battery drain)

i recently purchased an s6 edge and updated it to 5.1.1 as soon as i got it.however i went to sleep on 100 percent and woke up to about 20 percent which is a massive drain in battery..the battery stats show ADROID OS on top of the list which is keeping the CUP active all the times and not letting the phone go in to sleep..i tried a factory reset but it did not fix the issue. i disabled most of the bloatware that did not fix the issue either..then i noticed that when i remove the sim card from my phone my phone goes in to deep sleep and battery life comes back to normal however when i plug in the sim card the phone can not go in to deep sleep again..any possible solutions?