I have RUT240 and it only works with legacy firmware (flashed via bootloader).
Any newer 7 version either does not work or it gets stuck when I click login.
Here is some info I collected by doing SSH commands which were recommended in other posts.
Have you tried updating to the newer firmware version before, or has your device always operated on the legacy firmware?
Just a reminder, to successfully upgrade the RUT240 from Legacy firmware (RUT2XX_R_00.01.14.1 and below) to RUTOS (RUT2_R_00.07.01 and up), you must first upgrade to the latest Legacy firmware (RUT2XX_R_00.01.14.3 and up) and then upgrade to the latest RUTOS firmware.