Hi, I am trying to merge paired-end illumina reads (read length: 101) .

I am using the command:
fq2fa --merge --filter sample_1.fq sample_2.fq sample.fa

I am getting:
terminate called after throwing an instance of 'std::logic_error'
what(): SequenceWriter::SequenceWriter() ostream is invalid
Aborted (core dumped)

I have done this with my previous batch of samples, and was able to merge the paired-end reads and then assembled them successfully. Since then my computer was wiped and so I have re-installed idba-master. Since re-installing, any command I use results in the same error.
I even tried to re-assemble a merged paired-end fasta file from my previous sequencing batch. The same error is occurring, even though I had successfully assembled it in the past.

Can anyone please help.