diff --git a/lib/db.js b/lib/db.js
index 6dc9778a..561e4fc6 100644
--- a/lib/db.js
+++ b/lib/db.js
@@ -49,6 +49,7 @@ const getDefaultSchema = () => 'ERROR_SCHEMA'
 const searchPathWrapper = (t, cb) => {
   return t.none('SET search_path TO $1:name', [getSchema()])
     .then(cb.bind(t, t))
+    .catch(logger.error)
     .finally(() => t.none('SET search_path TO $1:name', [getDefaultSchema()]))
 }
 
diff --git a/lib/pairing.js b/lib/pairing.js
index 72e88f4c..ebedc001 100644
--- a/lib/pairing.js
+++ b/lib/pairing.js
@@ -32,7 +32,8 @@ function unpair (deviceId) {
         const q2 = t.none(`DELETE FROM machine_pings WHERE device_id=$1`, [deviceId])
         const q3 = t.none(`DELETE FROM machine_network_heartbeat WHERE device_id=$1`, [deviceId])
         const q4 = t.none(`DELETE FROM machine_network_performance WHERE device_id=$1`, [deviceId])
-        return t.batch([q1, q2, q3, q4])
+        const q5 = t.none(`DELETE FROM machine_diagnostics WHERE device_id=$1`, [deviceId])
+        return t.batch([q1, q2, q3, q4, q5])
     })
   )
 }
diff --git a/migrations/1724242113482-drop-last-used-fkey.js b/migrations/1724242113482-drop-last-used-fkey.js
new file mode 100644
index 00000000..3c3b62d7
--- /dev/null
+++ b/migrations/1724242113482-drop-last-used-fkey.js
@@ -0,0 +1,12 @@
+const db = require('./db')
+
+exports.up = function (next) {
+  db.multi([
+    'ALTER TABLE customers DROP CONSTRAINT customers_last_used_machine_fkey;',
+    'ALTER TABLE machine_diagnostics DROP CONSTRAINT machine_diagnostics_device_id_fkey;'
+  ], next)
+}
+
+exports.down = function (next) {
+  next()
+}