Do you have access to the season too? Or just to continue playing?
I’m on PC which is working.
It appears to be in season 33. I was able to get the challenge rift reward but unable to access the season 33 challenges. Hahaha. So who knows.
The only change that has happened for me is now instead of letting me create a seasonal character and then changing it soon as it’s made. Now it just says seasonal characters creation unavailable
Did you perhaps create a non seasonal character. You need to be online to create a seasonal character. Non season works fine. Challenge rifts always playable, you can however only get the reward once a week on one character whether it is a seasonal one or not.
All items, gold and paragon lvls are gone, this has been transfered to eternal. Even the season journal is reset from complete to nothing completed at all. This is all stored locally on the switch instead off online and when the season got restarted, this data could not be restored.
It just converted my non season chars that I was playing this season back to seasonal and that caused the issue because the game still thinks it a non season level 70 character. I wonder what happens when the season ends again… I hope my chars will be playable again, Blizzard should know they are not able to rollback savedata from console, they could not even offer support for the game on switch when I contacted them in the past.
I’ve tried every which way around I make a seasonal character and as soon as I hit accept it says it’s a non seasonal. I’ve tried rebirthing that doesn’t work either. No matter what I do I can only make non seasonal characters . I can play challenge rifts but nothing season . And I’m online. It’s been a 5 days I’ve tried twice a day no change 
Yeah, the only thing you can do is play non season if your characters are unplayable.
The only thing you can do is play on a new nintendo account, restore a cloud save from before the reset ( you will not be able to do this on xbox since it automatically syncs the save data) or play on PC if you want to play the rest of this season.
I will wait for next season, hopefully I have my PC fixed by then 