Error 55 means that the device is no longer accessible in the system. Windows "dropped" it as it did not respond properly for the system.
Yes, then the test can be stopped as the software may not access further areas until the reset (power on/off cycle) of the device.
Is it an external (USB) device? It happens more frequently on some USB devices because of the USB bridge chip which does not allow too much time for the device to respond. Quote from the Help -> Hard Disk Tests -> Surface test topic:
"It is possible that the disk controller or its driver may disconnect the not responding disk so it disappears from the system. This is more likely possible with USB connection. If this happens, it is recommended to connect the hard disk directly to the motherboard or a different controller and start the test again."
Maybe you can try to restart the test (after re-connecting/re-starting the device or the system if neccessary) from the beginning of this area by setting the "First block" to 5000 after selecting -> File -> Surface test -> Configuration in this window prior starting the test.
This way you can verify if the same issue happens again and at the same position.
(Tip: on this Configuration panel of the surface test you can also set Repeat count to eliminate the temporary slower transfer times (darker green colors) measured at the beginning of the disk, which may caused by the OS or other software).
If you are interested about all possible (system) error codes, please check:
(The most common ones regarding to hard disks and storage devices are 1, 55, 121, 1117 and 1167.)