The Roku 3 is a very old device. While it is still officially supported by Roku, in reality some apps simply won't work correctly on them any more. There are two versions of the Roku 3, the 4200 released in March 2013 and the 4230 released in April 2015. So it's either almost 10 or almost 12 years old. Honestly, it's time for an upgrade.
Dan
Roku Community Streaming Expert
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