Hi Navya,

This is not an answer to your question. Just provide some information.

In my case, when using the following site type

```
sites = [
if mod(n,3) == 2
Index([QN()=>2]; tags="S=1/2, Site, n=$n")
else
siteind("Fermion", n;conserve_qns=true)
end
for n = 1:3*ns
]
```

and `randomMPS(sites,state,10)`

, I obtain the following warning:

Warning: MPS center bond dimension is less than requested (you requested 10, but in practice it is 1. This is likely due to technicalities of truncating quantum number sectors.

And I find the fermion number distribution is the same as given, i.e., there is no randomness in the fermion sector. However, the spin sector is indeed random.

Instead, if I use the following site type

```
sites = [
if mod(n,3) == 2
Index([QN()=>2]; tags="S=1/2, Site, n=$n")
else
siteind("Fermion", n;conserve_nfparity=true)
end
for n = 1:3*ns
]
```

The good news is that now the fermion sector also becomes random (by checking the fermion number distribution), however, it seems that the fermion parity is not conserved! In fact the total number of fermion is found to be a non-integer.

Note, in my own project, the first site type and an essentially non-random (in the fermion sector) state `randomMPS(sites,state)`

are used, and it is so far so good :)

Best,

Junsen