We are using lightstreamer, beside other things, to send android notifications using lightstreamer mpn module. It worked mostly with no problems, but now we started to get this exception when trying to send notification:

Internal exception caught while sending notification: GCM service error: MismatchSenderId
com.lightstreamer.h.k: GCM service error: MismatchSenderId
at com.lightstreamer.h.d.n.b(n.java)
at com.lightstreamer.h.d.n.b(n.java)
at com.lightstreamer.h.d.s.d(s.java)
at com.lightstreamer.l.c.aj.b(aj.java)
at com.lightstreamer.l.c.aj.run(aj.java)
at java.util.concurrent.ThreadPoolExecutor.runWorker( ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:617)
at com.lightstreamer.l.c.aw.d(aw.java)
at com.lightstreamer.l.c.ax.d(ax.java)
at com.lightstreamer.l.c.av.run(av.java)

We checked everything and senderID and server api key have correct values

We are using
Lightstreamer Server Allegro-Presto-Vivace version 6.1.0 build 1817
Android client 1.2