5GEE VPN pass through (L2TP over IPSEC) ???

[Happytoon]

Is there any issues with running an L2TP IPSec tunnel over the EE mobile network???
My Wife and I are working from home.  We have 5GEE as our main home broadband (as the fibre doesn't get to us!).
I can work over my SSL VPN with no issues and can access remote/shared folders on my work servers.
My wife had a new laptop and her company set up the VPN with a L2TP IPSec tunnel. She can not connect to her servers at all. The VPN Client (Draytek Smart VPN) report the connection successful, yet we can't see nor ping any servers from her laptop. The VPN works fine for all her colleagues (but I assume that they have a proper wired/fibre broadband). 
Is their any issues/limitation on running VPN Tunnel over the EE network???
As anyone manage to run a L2TP IPSec Tunnel over mobile data?
Please help and point me in the right direction as currently she is working mostly from the office with very long commute.
Thanks in advance
Tony

[EssexBoyEE]

You may have some issues with this, as a few 4/5G Router Users do run into problems using VPNs this way.

One thing you could try is to set the 5G Routers APN Profile to a Fixed IPV4 Only (rather than IPV4/6) and set the Authentication to PAP rather than Auto, depending on the Router Make your probably going to need to create another APN Profile rather than edit the existing one.

Another thing you could try within the Profile is set the User (eesecure) to nothing, leave it Blank and do the same to the Password (secure) also leave Blank.