Sorry to say I have the same situation, except I have two TCL series 4 Roku TVs. One is 32" the other is a new 65". The 32" still works fine with the Roku app. The 65" worked fine for one week with the app. Then the 65" stopped working with the app couple days ago. I applied and verified all the same solutions and settings, plus restored the 65" to factory settings and started from scratch. Just wanted you to know you're not alone.