# Demultiplex-problem

**URL:** https://forum.qiime2.org/t/demultiplex-problem/11719
**Category:** Technical Support
**Created:** [September 28, 2019, 4:31pm UTC](https://forum.qiime2.org/t/demultiplex-problem/11719 "2019-09-28T16:31:03Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![heavennew](https://forum.qiime2.org/user_avatar/forum.qiime2.org/heavennew/32/936_2.png) [@heavennew](https://forum.qiime2.org/u/heavennew)
#### Post date: [September 28, 2019, 4:31pm UTC](https://forum.qiime2.org/t/demultiplex-problem/11719/1 "2019-09-28T16:31:03Z")

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I have the 16S illumina data and want to analysis with qiime2.  
But have some problem in the demux step.  
the data type is emp-paired.

the bug information:  
Plugin error from demux:

Mismatched sequence ids: M03364:232:000000000-BBHLB:1:1101:14416:1335, M03364:232:000000000-BBHLB:1:1101:13167:1335, and M03364:232:000000000-BBHLB:1:1101:13167:1335

Debug info has been saved to /tmp/qiime2-q2cli-err-rcuf19hy.log

I don't know how to deal with it?

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### Author: ![ben](https://forum.qiime2.org/user_avatar/forum.qiime2.org/ben/32/1790_2.png) [@ben](https://forum.qiime2.org/u/ben)
#### Post date: [September 28, 2019, 7:01pm UTC](https://forum.qiime2.org/t/demultiplex-problem/11719/2 "2019-09-28T19:01:32Z")

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This seems similar to this problem described here:

> [@New to Qiime2 Mismatched sequence ids](https://forum.qiime2.org/t/new-to-qiime2-mismatched-sequence-ids/2050/11):
>
> Thanks @megladds! I cracked open your files, and found the following first three ids in each file: barcodes: @M01522:85:000000000-AU4UD:1:1101:19131:1345 2:N:0:2 @M01522:85:000000000-AU4UD:1:1101:16978:1376 1:N:0:2 @M01522:85:000000000-AU4UD:1:1101:18361:1378 2:N:0:2 forward: @M01522:85:000000000-AU4UD:1:1101:19131:1345 1:N:0:2 @M01522:85:000000000-AU4UD:1:1101:18045:1364 1:N:0:2 @M01522:85:000000000-AU4UD:1:1101:16978:1376 1:N:0:2 reverse: @M01522:85:000000000-AU4UD:1:1101:19131:1345 2:N:…

Do you have access to your sequencing facility to ask them about this problem?

Ben

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<div class="post-metadata">

### Author: ![heavennew](https://forum.qiime2.org/user_avatar/forum.qiime2.org/heavennew/32/936_2.png) [@heavennew](https://forum.qiime2.org/u/heavennew)
#### Post date: [September 29, 2019, 8:38am UTC](https://forum.qiime2.org/t/demultiplex-problem/11719/3 "2019-09-29T08:38:20Z")

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Hi ben,

Thank you for your reply.

I checked my data. as you said, total number of forward and reverse sequences are different to barcode sequences.

I will contact to the sequencing facility.

Thank you!