Hello, I am using DESeq2 to perform differential expression analysis. I have forty samples, gender and age are the variables in my colData. However, when I ran the code, it gave me the error that " the model matrix is not full rank". Initially, I thought it is because there's a sample that has a missing value in colData, so I removed that sample from dds and colData, but the error still exists. I read the vignette section of "Model Matrix not Full Rank", and I think the problem I am having probably matches the "levels without samples" condition (Like there's no certain age in the Female or Male group), but I am not really sure. Could you please help me check my design and see if I need to remove the columns of 0 manually from the model matrix?

dds= DESeqDataSetFromMatrix(countData = cts,
                              colData = colData,
                              design = ~ Sex + Age
                             )

as.data.frame(colData)

            Age    Sex
          <fctr>.   <fctr>
sample_01   17      F       
sample_02   16.1    M       
sample_03   10.4    M       
sample_04   15.3    F       
sample_05   14.5    F       
sample_06   18.1    M       
sample_07   14      F       
sample_08   15.6    F       
sample_09   11.1    F       
sample_10   9.5     -