NA values in LIS SoilMoist_inst

[shaider2]

Hi,
I am running LIS for 3 years and I am using Noahlsm. For the instantaneous soil moisture I have some NA values in the data. Do they represent waterbody?
For WRF input what is the value of water body in SMOIS (instantaneous soil moisture)? Is it 1.
Are the mask of waterbody for LIS and WRF same?
It will be really kind if I can get some suggestions or source where I can find these answers