Google Fit activity logs

Hello everyone, I linked my Google Fit to MFP to log steps, but Google Fit also tracks my walks and bike rides and passes them onto MFP. However, they're way off. For example, I bike to work in about 15min a distance of 2km,which is an average speed of about 4kmh. However, when it's logged into MFP, it's logged as 15min of 19-23kmh biking! This in time causes my exercise calories to be way higher than they should! Any suggestions? Also, I manually logged a swim on Fit with the calories and that, and the logged swim in MFP was lower than that. Any ideas? Much appreciated!