Hello Siddharta,
you need to decide if you want to have OSPF running only on the GRE tunnel you need to remove the network command con the ip subnet of the serial link.
In fact you have:
network 10.10.54.0 0.0.0.255 area 0
that is the WAN interface to HQ
network 192.168.10.0 0.0.0.255 area 0
on R2 router under ospf I don't see the
network 192.168.10.0 0.0.0.255 area 0
there is
network 192.168.0.0 0.0.0.255 area 0
and
network 10.10.54.0 0.0.0.255 area 0
I would do the following changes
remove on both routers
network 10.10.54.0 0.0.0.255 area 0
add on R2
network 192.168.10.0 0.0.0.255 area 0
this creates an OSPF adj on the GRE tunnel.
Otherwise you could risk negative effects in having ospf enabled on both the GRE logical link and the physical link
to troubleshoot OSPF adjacencies you can use:
terminal monitor
debug ip ospf adj
Hope to help
Giuseppe