Concatenated SMS in PDU using Raven

Hi all,
Im wondering if this is at all possible as my Raven H5223E-W seems to restart whenever I try to send a PDU with a UDH in it.
I have followed the guide but if I copy paste even the examples into my putty terminal the router seems to come out of passthru mode and hangs before coming back online a few minutes later. I have a screenshot of what is going on to see if anyone can see anything wrong.

thanks Callum

Are you able to send normal PDU sms (i.e. without UDH header)?