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It maybe worth trying a different power supply with the SureSignal (Version 1 & 2 ), even if it still looks ok regarding lights etc as there have been some reports of replacement power supplies solving the issues as they can degrade. They are available on eBay for around £10.
From member cineriv "But firstly, have a look around for a suitable unit with a 12 Volt output @ around 1.5Amp capacity that you could 'borrow' to prove the fault. Suitable units can be found on external hard drives, monitors, printers, routers etc.etc."
If it's a Version 3 then unplug it now and ask customer service to help you under the 24 month guarantee. If it's out of warranty then I've seen that as this is a known issue with the v3 then they are still helping people.
Current Phone > Samsung Note 9 _512Gb > Model: SM-N960 Hybrid-Duos.
Samsung One Ui / Pie.
Samsung Gear s3 Frontier Watch.
I'm sorry to hear you're experiencing difficulty connecting to your Sure Signal @Minb. I can see @BandOfBrothers has provided you with a link to our troubleshooting guide. If you're unable to find a resolution to your issue there, follow the steps advised under the Issue not listed header and we'll be in touch.