If you use the Stryd app to record your run, make sure it is not using the GPS of the phone. The GPS of the phone is not as accurate and will give you incorrect pace and distance. In settings of both the iOS and Android app, you will find a setting to set Stryd as the speed source.
If Stryd is in a white font, with an orange background, it has been selected correctly to provide accurate distance and pace. Below an example screenshot from the Stryd app for Android:
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