Wierd basecamp route after downloading to Garming GPSmap65s

Dear all,

I just purchase a GPSMAP65s and try to use Basecamp.

I have download an OpenStreetMap to my GPS from BaseCamp

Then I have define a test root that I define in Basecamp.

Then I send the Test root to my device

Then I start my device then go to FIND > ROUTE and select my Test trace to GO.

What I have notice is that in BaseCamp, my route are perfectly draw above route BUT when I look at the root on my device after transfert, at some point the root is completely off road on real area you cannot go

Any idea what could be this lack of precision after downloading the route to my device ?

You can see the difference in file below

https://1drv.ms/u/s!AuPzV8ZG3v-2llKSDybbg9YY7qLW?e=1FKrRn

Regards