Ride to 100 has stopped registering my miles

No, doesn't work. Ive just input the ride as a manual activity. Put in the exact stats from the zwift ride, every detail and the 24 miles haven't been added on to the 2 challenges. Something has gone drastically wrong with garmin. People have worked hard on these cycling ones and no distance is being updated even on manual entry. I dont get it. I only hope garmin get this sorted asap

No, doesn't work. Ive just input the ride as a manual activity

As I wrote, the activity must be recorded by a Garmin device. Manually created activities are not recorded by a device. That always worked like this.

The ony way you can cheat the system, is recording a dummy activity (just a few secs), and then editing it accordingly - although it is practicaly the same as a manually created activity, unlike that, this one will be accepted.

The question is, though, how long it will take Garmin to plug this hole too, so I would not rely on it for future, and rather be recording the activities correctly in their full length with a Garmin device.

OK but have garmin said why this has happened. Its not fair that they've done this, if its not a mistake or error that is, so why have my miles disappeared and why are they no longer counting towards the challenges??

Its not fair that they've done this

Quite oppositely, this is finally fair, since unlike imports from other apps, Zwift was in an advantage, while the hole was open.

so why have my miles disappeared and why are they no longer counting towards the challenges??

Because they were not recorded by a Garmin device as the badge conditions require (and always did). Zwift used a security hole, allowing their rides to be counted. It is now plugged.

OK I get that but having all those miles removed is just soul destroying! Those miles could have been allowed to stay!!