Apple Watch not closing exercise ring.

Hi, I hope someone can help. I’ve looked but can’t find an answer to

this.

I decided to upgrade from my Fitbit to an Apple Watch SE. Quite impressed with it until it came to closing the exercise rings. I have arthritis in my back and joints so walk quite slowly. 

I set it for my outdoor walk on Wednesday which was 49 mins, but my exercise circle only recorded 3 minutes and another 2 mins for the rest of the day. This is happening every day. 

I know I’m slow at walking, but wouldn’t have thought it would make a difference as long as I am doing it. 

Ive attached an image of the 5 minute one. 

Does anyone know of some way of making it record correctly? Surely Apple are not discriminating against those of us who are less able.