Dynamic Interfaces (sstp) made static on OSPF disappear

Hello community,
We have OSPF over a SSTP link. Such interfaces are fixed static on OSPF->Interfaces in order to chage default cost to a fixed one.
When SSTP falls down because any failure, it becomes unknown in OSPF->Interfaces. Then, when SSTP goes up again, it appears as a dynamic Interface with default cost ignoring the previous static interface created for SSTP.

RB1000 v5.21

add static entry in “/interface sstp-server” menu

YOU ARE RIGHT thank you very much.