diff --git a/conf/modules.config b/conf/modules.config
index 28ede9d..8f1291a 100644
--- a/conf/modules.config
+++ b/conf/modules.config
@@ -350,7 +350,7 @@ process {
 
     withName: KRAKEN2_KRAKEN2 {
         ext.args = params.kraken2_save_minimizers ? { "${meta.db_params} --report-minimizer-data" } : { "${meta.db_params}" }
-        ext.prefix = params.perform_runmerging ? { meta.tool == "bracken" ? "${meta.id}_${meta.db_name}.bracken" : "${meta.id}_${meta.db_name}.kraken" } : { meta.tool == "bracken" ? "${meta.id}_${meta.run_accession}_${meta.db_name}.bracken" : "${meta.id}_${meta.run_accession}_${meta.db_name}.kraken" }
+        ext.prefix = params.perform_runmerging ? { meta.tool == "bracken" ? "${meta.id}_${meta.db_name}.bracken" : "${meta.id}_${meta.db_name}.kraken2" } : { meta.tool == "bracken" ? "${meta.id}_${meta.run_accession}_${meta.db_name}.bracken" : "${meta.id}_${meta.run_accession}_${meta.db_name}.kraken2" }
         publishDir = [
             path: { "${params.outdir}/kraken2/${meta.db_name}/" },
             mode: params.publish_dir_mode,