TACX Software , IMPORT GPS ( GPX ) file... road feeling error / GPS error

Hi all

I have a huge error....

1. I´m going in on GARMIN CONNNECT, and getting my ROUTES that i have ride outdoor many times. DONWLOAD the GPX file.

2. Upload the GPX into " TACX software program " on line as a GPX file, and choosing " Mobile phones " for the best output...

3. When I start my GPS route from Ipad ( TACX PROGRAM ) and starting ride... THEN when I´m going down a hill the AVG % saying going up.

So it looks like I´m long ahead the GPS on the Neo bike, and the GPS is behind, so nothing fit the map...

Any one tried this ???

this must be a big issue, and i tried many routes

https://ibb.co/3FFg44w