The Pro-433 might need all the site channels programmed in, rather than just the control channel. Do you have all 12 frequencies programmed in, in order, or just the highlighted one (866.100)? They might have even changed their control channel to another frequency.
When you scroll through the frequencies manually, one should have a constant data sound to it (the control channel). All the others should be silent until a voice channel rolls through them and you get a snippet of voice, then the conversation switches to another frequency. Can you hear voice on any of these frequencies if you pause on them for awhile?
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