@catherineparker
If your Hisense RokuTV is no longer under warranty, you can try purchasing a wifi module like this one https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313&_nkw=43h4030+wireless+module&_....
It basically just plugs into the board and you should be good to go again.
The wifi module listed for your TV is Hisense 58R6E WIFI module (goes into other models as well). The module part number is also referenced generically as WCOHR2601.
Generally, a good idea to actually look at the part number of the existing module before ordering, just in case the manufacturer used or changed part numbers.
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You can try a Factory Reset on your RokuTV to see if that helps fix the issue, but usually is a matter of a bad module or a bad grounding wire/solder point on the module itself.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102
