Navmesh object follows strange path to destination

Hello. my first time posting. I am using Unity 2020.3.14f1 Personal. I have 2 navmesh surfaces and an animal I want to walk from a starting point to a destination. I draw a white line as you can see in the linked image, in the game and scene views. The animal starts in the 'entrance' surface which is connected to the main surface via a navlink. The path on the main surface, shown in white, is not direct but seems to go along the edges of the navmesh areas. Why does it not go straight through a navmesh area to take a direct route. There are no obstacles. Any advice would be great. Image: https://1drv.ms/u/s!ApN4Ed0sLAE7gmECDa3gJs-lVRZo