I have the same issue , with my roku streambar edition. I put it in my daughter bedroom and I am tired to go there and restart roku device in order to work properly . My home wireless is Netgear Orbi Wifi Mesh , a powerful and strong wireless system. All my other devices are working flawless on this network never had an issue. Just for "fun" I brought a new wifi router and configure it only for roku streambar near that device and the same result. I turned off all wifi devices I have and kept only roku, the same result. So please come with a solution not with all "copy-paste" troubleshoouting like : disconnect, reconfigure, etc. My wifi mesh is one of the most expensive and best wifi systems a house can have. Please come with a solution, an update, e.t.c.
After long searches I found some solutions which can help us fixing the issue with roku(the link is not malware, virus or other forms of internet harming, i show this link because I am tired, like you guys, to keep ask roku support team to help me and I hope the moderators from this forum will accept this link such as, thank you):
https://techprofet.com/roku-tv-keeps-disconnecting-from-wifi/