I can imagine how frustrating it must be to not get service in the basement of your building. Although we do not guarantee service will work indoors (basement) due to signal-blocking materials in the homes. We can definitely troubleshoot to finding a possible resolution for you. Is the no signal constant or random? Has the signal worked in the basement in the past? Is there a big difference in service when you go outside? Is it the same no service with other Rogers devices in your basement, (friends or relative with Rogers)? What have you tried so far? What type of phone do you have? Depending on your device you may have the option to set the network type to Edge / GSM only, these settings tend to be more stable.
For cellular signals blocked due to building structure, the most common solution most people go with are cellular signal boosters. Theses boosters are designed to extend and Increase the signals in the home which should improve signal coverage in 1-2 rooms, users normally run an online search to find a suitable cellular booster for their home.