@amona121
The Roku Express LE is a 2.4ghz-only device. Depending on your network setup, the 2.4ghz band may have been disabled (or the 2.4ghz radio is not broadcasting).
Regarding your phone's hotspot, you may just have to toggle on the 2.4ghz band.
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If you decide to just upgrade, the Roku Express 4k+ is currently on sale for $30. Should be able to find it at Walmart, Target, Best Buy for this same price that is advertised on the Roku website. The Express 4k+ is dual-band (both 2.4ghz and 5ghz) so you may find this the easiest route.
https://www.roku.com/products/players
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However, if you speak to whoever is in charge of the church network, maybe just verify that the 2.4ghz band is Enabled, the Wireless Mode is set to b/g/n. and they are using a Wireless Channel between 1 and 11 if you want to try again the Express LE. Also, by using the 2.4ghz on your mobile hotspot, you should be able to get the Express LE to connect, but likely would not want to stream in that manner as the data usage may quickly use your hotspot data allowance.
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