IPsec VPN change WAN connection

Hi all,

We are trying to move an IPsec VPN over from one WAN connection to the other on a FGT100D, with a different ISP and thus a different public address. We reconfigured the VPN both ends, but it won't re-establish. Running diag debug ike -1 shows that the firewall still has the old connection in memory, and tries to continue to use it. When it tries to initiate over the new address, an error is shown:

duplicate connection detected on name insert, dropping this connection

I have seen the messages from ede_pfau about the black hole routing, but I am unsure how to make this work successfully. There's apparently no way to silence the connection attempts, reset the connection, or have it quiet down.

I have tried to disable the policies and disable the routes, both ends, and re-enabling them, but this had hardly any effect.

Reconfiguring the old WAN address and WAN interface specification on both sides of the VPN connection to what it was before re-enables the VPN immediately to its active state.

Any suggestions?