In case this is a Strava problem can you please describe it?

What do you mean “race track”?  Are you referring to running on a treadmill? 

If so, the issue isn’t likey anything connected to GPS tracking, it is tracking your steps.  For most watches, this needs to be calibrated through the watch itself.  Garmin watches have an option when you finish your run (when you record in the treadmill activity setting) on the treadmill to calibrate and save where it will ask you to enter the distance from the treadmill readout so it can match.  The watch should “learn” your stride and be more accurate in the future.

“Race track” sounds like a stadium running track / 400 m oval, some gps devices tend to have problems there and don't work accurately (the recorded path isn't an oval but rather zigzagging across the field).

If that's what ​@Lucas Heavy means, then the solution would be using a watch to record the runs (not a phone), preferably one that has the capability of capturing the track runs correctly. Personally I’m using an Apple Watch, it has a Track Detection feature - when I start an outdoor run recording on a track, or when I arrive there running, the watch automatically detects that and asks me to confirm the lane which I want to run in. The resulting recording is a smooth oval with a precise distance per lap (400 m for the 1st lane, 407 m for 2nd etc). Perhaps other watches have something similar, but I only know about AW.