What page are you starting from?
If you are using a mobile browser, try a desktop browser or the eBay app to send a message. Or a different browser. Some browsers are better than others when it comes to certain types of redirection.
Try another link from a different page -- order details, order page, selling overview page. Note that some of these old links may point to a newer page.
Seller Hub Overview:
https://www.ebay.com/sh/ovw
If the Selling Overview page is giving you problems, try these direct links:
Orders (https://www.ebay.com/sh/ord)
Active listings (https://www.ebay.com/sh/lst/active)
Marketing (https://www.ebay.com/sh/mkt)
Performance (https://www.ebay.com/sh/prf)
Payments (https://www.ebay.com/sh/acc)
Research (https://www.ebay.com/sh/research)
Alternate links
New All Selling:
https://www.ebay.com/sh/allselling/listings
Selling Overview:
https://www.ebay.com/mys/overview
Old All Selling:
https://my.ebay.com/ws/eBayISAPI.dll?MyEbay&gbh=1&CurrentPage=MyeBayAllSelling&ssPageName=STRK:ME:LN...
Old Sold:
https://my.ebay.com/ws/eBayISAPI.dll?MyEbayBeta&CurrentPage=MyeBayNextSold&ssPageName=STRK:ME:LNLK:M...
You may be able to compose a new message from the user's feedback or profile page.
