For all the time three such devices were bought, for myself and neighbors. The first two died after a year of use. The power indicator is on and that's it. Not repaired in any way. Then we bought another such toy from Yota, a year of use has passed, the reboot helps or wait a couple of minutes and over time more and more often. There is Internet for five minutes, you wait for two. No firmware helps, the problem is in the hardware itself. I would say not even a problem, but an engineering development that provides for a one-year warranty. I do not advise you to buy, because I think it is unreasonable to pay 6-7 for one year of modem "rent" :)
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