diff --git a/pom.xml b/pom.xml
index a0b550299..588824368 100644
--- a/pom.xml
+++ b/pom.xml
@@ -291,7 +291,7 @@
       <dependency>
         <groupId>org.signal</groupId>
         <artifactId>libsignal-server</artifactId>
-        <version>0.21.0</version>
+        <version>0.18.0</version>
       </dependency>
       <dependency>
         <groupId>org.apache.logging.log4j</groupId>