ERROR: long vectors (argument 1) are not supported in .C [in call to 'silhouette.default'] with R package NMF

Question

Currently I'm running r version 3.6.0 (2019-04-26) on a debian server with 264 GB memory and Intel(R) Xeon(R) CPU. Now I'm trying to run the nmf calculating for a about (5*10^4) * 1100 matrix, it works well when I set a specific rank, such as:

m1<-nmf(df.aa,rank=4,nrun=1, seed=123456,.opt='vP')

it returns:

NMF algorithm: 'brunet'
NMF seeding method: random
Iterations: 2000/2000 
DONE (stopped at 2000/2000 iterations)

However, when I tried to set a series of rank numbers, such as:

m2 <- nmf(df.aa,rank=c(2:3),nrun=1, seed=123456,.opt='vP')

then it threw an error:

    Compute NMF rank= 2  ... + measures ... ERROR
    Compute NMF rank= 3  ... + measures ... ERROR
    Error in (function (...)  : All the runs produced an error:
      -#1 [r=2] -> long vectors (argument 1) are not supported in .C [in call to 'silhouette.default']
      -#2 [r=3] -> long vectors (argument 1) are not supported in .C [in call to 'silhouette.default'] ```

I'd say it quite annoyed me a little bit... I did some researches in internet but still have no idea how to fix it. Maybe the reason is that I did hit some memory limits of nmf package itself, or it just hit the limit of memory of the sever itself? Any info will be much appreciated.

    dim(df.aa)
[1] 54293  1091