I have set the route colour to red and then blue but it always shows purply/pink colour also there are some red lines what are these for get confusing on a small screen I just want to see a route in colour of choice

Nonetheless the route lines look odd, would be better to see what the actual activity map looks like as both of the photos don't seem to be an actual ride, in the first the GPS fix has not occurred and no chevrons are evident and the second is more a map browse than an activity and the larger chevrons would indicate "Turn Guidance" is disabled or has not been applied to the route. (I hate the doubled chevrons on out & back two way routes, most confusing, sometimes suppressed & some not and you would think Garmin has the smarts to figure the direction of travel and only show the appropriate chevrons.) Notwithstanding "MapTheme" customisation the route lines are difficult to see for us "mature" riders, the calculated line (not on any of these pictures) is always wider so why can't we make the route wider especially if not using Turn Guidance. (line width/scale is available on Garmin car nav devices via the MapTheme)

The red lines look more like "always display" courses than history lines?

Navigation > Courses > Select Course > Course Settings (3 dots upper right of screen) > Always Display ?

what is your software version, the line cutting the corner in picture 2 could be the “lock on road” bug prior to 17.29?