diff --git a/modules/rhizo_base/files/SysmoBTS/ca-fix.sh b/modules/rhizo_base/files/SysmoBTS/ca-fix.sh
index d4229e6..4e43bbd 100644
--- a/modules/rhizo_base/files/SysmoBTS/ca-fix.sh
+++ b/modules/rhizo_base/files/SysmoBTS/ca-fix.sh
@@ -5,5 +5,6 @@ grep isrgrootx1.pem /etc/ca-certificates.conf && exit
 wget -q --no-check-certificate https://letsencrypt.org/certs/isrgrootx1.pem -O /usr/share/ca-certificates/isrgrootx1.pem
 sed -i '/^mozilla\/AffirmTrust_Commercial.crt/i isrgrootx1.pem' /etc/ca-certificates.conf
 sed -i '/^mozilla\/DST_Root_CA_X3/s/^/!/' /etc/ca-certificates.conf
-update-ca-certificates
+/usr/sbin/update-ca-certificates
+