I know… Many posts about this issue - sorry. Just couldn’t decide where to write my own issue.
I’m new to Zwift and registered on ZwiftPower yesterday, opt’ed in and everything. All good so far. I can even see my total distance in ZwiftPower.
But! Can’t see my rides though - and have been waiting for possible sync since yesterday. Nothing showing.
What can be the reason?
Have a NICE Friday all of you 
Only Events ridden since joining Zwiftpower are shown in the Event main results. All rides including Events are shown in your Activities list (found under Profile tab) but may need updating via the “update” button. I’m not sure if this pulls activities prior to joining Zwiftpower though.
If you rode in an event since joining Zwiftpower, let us know the event ID (as well as your own ZP ID).
Cheers
You have not done any events so there will be no data on the main page. but as Dean said there should be activities listed in the activity tab.
I joined ZP yesterday. Had 3 rides prior to that - and 1 ride just now (activity 910853457009704992)
ZP-ID: 4360855
There’s still nothing to see in ZP.
That one is not an event, neither are your previous rides. It will appear in activities list which is found under your profile tab in Zwiftpower but under the Event list which is the default view when viewing your profile.
Not sure if you know this or not but here’s Zwift’s guide for joining events, but I’d also suggest an easier way to view events is searching through this 3rd party site that a lot of us use.