Vodafone network rejections when switching cell towers

[Geert Lens]

Hi,

We are experiencing network rejections when our device switches from cell
tower to cell tower.

We have been in contact with our SIM provider, Vodafone, which says that
this is due to us sending delete and create session requests too rapidly
(within 40ms between requests).

These are Vodafone's comments on the Wireshark trace (see attached) they
have captured on their side:
===






*As can be observed in the shared traces, the new create session request
was initiated after less than 40ms since the Delete Session. Also, it is
visible that the session was not terminated internally, the Credit Control
Terminate messages for the initial data session were sent after the Create
session Request. Moreover, this SIM is having static IP allocation. Even if
the IP is not assigned by the PGW, after a data session is closed, the IP
assigned for that data session is set in quarantine for a specific period
of time ( not configurable, it is calculated internally by the PGW). Based
on the above, the reason why the session got rejected is due to the short
period of time between Delete and Create. *
*===*

Is this a known problem? And is this something we could configure on the
device/modem side?

Thanks in advance for any insights on this matter!

Some additional info...
We use NetworkManager to setup the connection with our private APN.
We are using MM 1.18.0 and libqmi 1.30.2 on Linux kernel 4.14.98
We are using the SIM7100E from Simcom which is running firmware
4534B06SIM7100E
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