diff --git a/devops-stages/stage-test.sh b/devops-stages/stage-test.sh
index bfcdf9bde9e9330669be31b35a095067bf13a043..23f2dd6893e2fb66c7543f33dc91617dd1a47733 100755
--- a/devops-stages/stage-test.sh
+++ b/devops-stages/stage-test.sh
@@ -14,6 +14,6 @@
 # limitations under the License.
 set -e
 echo "Launching tox"
-tox --parallel=auto
+tox
 
 
diff --git a/releasenotes/notes/single_tox_environment-30aaca72e8b59c4e.yaml b/releasenotes/notes/single_tox_environment-30aaca72e8b59c4e.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..3730af4741f7e12d677b83e558b4f04731c5c65c
--- /dev/null
+++ b/releasenotes/notes/single_tox_environment-30aaca72e8b59c4e.yaml
@@ -0,0 +1,23 @@
+#######################################################################################
+# Copyright ETSI Contributors and Others.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#######################################################################################
+---
+other:
+  - |
+    Running several tox environment parallely causes failures during stage tests frequently. 
+    Although the reason is not clear, we are suspicious that environments are affecting each other.
+    This change allows to run only one tox environment at the same time.
+    
diff --git a/tox.ini b/tox.ini
index b9cbdb65c6c851951e4d4b7e79f548fe2033f022..f48234af4975d3e06634eb06890d84d411a10615 100644
--- a/tox.ini
+++ b/tox.ini
@@ -20,6 +20,7 @@ envlist = black, flake8, safety, cover
 
 [tox:jenkins]
 toxworkdir = /tmp/.tox
+setenv = XDG_CACHE_HOME=/tmp/.cache
 
 [testenv]
 usedevelop = True