When you use a USB modem, you are given some amount of traffic, after which the speed is on unlimited tariff drops sharply. Depending on the region, operator and tariff, conditions will vary. To restore speed, use USSD commands to connect service “Extend speed”: Beeline — *110*311# (call); Megaphone — *105*906# (call) for Moscow region, details for others You can see the official website; MTS — 0890 (reference for the call from SIM card), 8 800 333 0890 (multichannel hotline phone). If you have a different operator, visit the official website to clarify the data on providing internet connection.
Some browsers, such as Opera, have a Turbo function. It is needed in order to increase the speed of page loading when connecting slowly. Check it out, you probably turned it off. If so, resume Turbo mode.
The download speed also depends on the server on which it is located. In case of problems and technical work on the site, the download speed may be reduced. Otherwise, the site may not be loaded at all. You need to wait a while, probably speed will be restored.
Check the validity of the modem. Examine your device settings if you have software attached to it. Perhaps the speed limit was laid out in the program.
If you use a torrent manager, the download rate will depend on the number of giveaways. If you haven’t changed the torrent manager settings, the speed increase will be observed with the addition of giveaways.