If you discontinue the approach then it must be assumed you will be positioned away from the approach course and then have another go? In this case the waypoints in the FPLAN will stop sequencing and Approach phase will remain. A second approach is available.
If you fly a missed approach in approach phase ( I.e. Don't activate missed approach by selecting TOGA), the missed approach waypoints are available to the end of the missed approach. The destination now has sequenced and disappears so to fly another approach you need to define a new destination and approach. Our FCOM is a little unclear on this so tried it in the sim and this was the result.