Strava distance is shorter than Apple watch due to device gps file issue

Hi,

I have recorded runs using Apple watch 3 and share the record in Strava.

My runs in Strava is shorter than my device starting from end of July'21. I reported the incidents to Strava and the customer service said this is due to my device gps file issue. The actual runs in Apple is 11.02km but transferred to Strava as 6 plus km.

I have unpair the watch and repair but the issue is not resolved.

I really like to use only Apple watch to record my exercise but due to this issue I have recently bought a Garmin watch instead because I am joining competition.

Also, last time i have the running map showed up in Strava but I no longer can see the maps in Strava sometime ago. This does not seem to be a big issue to me but the distance does matter a lot.

Kindly assist. Thanks