7750 NAT with defailt-route

[serenchik]

Hello,
I configured NAT on 7750 (I'm making a test lab on VSR for further deployment on hardwar, TiMOS 21) and specified destination-prefix 0.0.0.0/0 in IPoE VPRN, where clients traffic arrived from BNG - config>service>vprn>nat>inside. BNG is connected directly to the 7750. 7750 connected to CORE. In this case, a situation that is unclear to me has arisen - if another default route arrives in this VRF where the NAT is located via MP-BGP - traffic from clients goes past the Nokia NAT and goes to the network core, and NAT does not occur (in this VRF is located another Juniper NAT, I want to make a reservation). If the default route that goes via BGP from Juniper is removed, clients go to NAT Nokia......

config>service>vprn# info
----------------------------------------------
bgp-ipvpn
mpls
auto-bind-tunnel
resolution-filter
ldp
exit
resolution any
exit
route-distinguisher 65001:100
vrf-target target:65001:100
no shutdown
exit
exit
nat
inside
nat-policy "CGNAT_POLICY"
destination-prefix 0.0.0.0/0
exit
exit
no shutdown
----------------------------------------------

I see the active static default route in NAT, but at the same time, while the default MP-BGP route arrives from Juniper, traffic passes NOKIA and ends up on Juniper NAT.

show router 100 route-table protocol nat extensive
====================================================
Route Table (Service: 1006400)
====================================================
Dest Prefix : 0.0.0.0/0
Protocol : NAT
Age : 03h28m24s
Preference : 0
Next-Hop : NAT inside
Interface : _tmnx_nat-inside
QoS : Priority=n/c, FC=n/c
Source-Class : 0
Dest-Class : 0
Metric : 0
ECMP-Weight : N/A
----------------------------------------------------
No. of Destinations: 1
====================================================