diff --git a/requirements-app.txt b/requirements-app.txt
index a464c6f73..12163b5e0 100644
--- a/requirements-app.txt
+++ b/requirements-app.txt
@@ -23,5 +23,5 @@ notifications-python-client==5.6.0
 awscli-cwlogs>=1.4,<1.5
 itsdangerous==1.1.0
 
-git+https://github.com/alphagov/notifications-utils.git@39.4.6#egg=notifications-utils==39.4.6
+git+https://github.com/alphagov/notifications-utils.git@39.6.0#egg=notifications-utils==39.6.0
 git+https://github.com/alphagov/govuk-frontend-jinja.git@v0.5.1-alpha#egg=govuk-frontend-jinja==0.5.1-alpha
diff --git a/requirements.txt b/requirements.txt
index 78ca4497f..c0dbe63e3 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -25,7 +25,7 @@ notifications-python-client==5.6.0
 awscli-cwlogs>=1.4,<1.5
 itsdangerous==1.1.0
 
-git+https://github.com/alphagov/notifications-utils.git@39.4.6#egg=notifications-utils==39.4.6
+git+https://github.com/alphagov/notifications-utils.git@39.6.0#egg=notifications-utils==39.6.0
 git+https://github.com/alphagov/govuk-frontend-jinja.git@v0.5.1-alpha#egg=govuk-frontend-jinja==0.5.1-alpha
 
 ## The following requirements were added by pip freeze:
@@ -33,6 +33,7 @@ awscli==1.18.82
 bleach==3.1.4
 boto3==1.10.38
 botocore==1.17.5
+cachetools==4.1.0
 certifi==2020.4.5.2
 chardet==3.0.4
 click==7.1.2