From the inside of the server you will not see how much bandwidth the provider has assigned for your VPS, since the limitation is set from the Node side, but not the VPS itself. If you have failed of contacting the support of the provider, then try analyzing the service details/management page of the service provider, since it would probably show general resource usage.
OVH VPS bandwidth monthly limit is 10TB. According to their TOS, they may limit your network connection if your bandwidth usage exceed this limit. But VPS only have 100Mbps connection, so even if you VPS download/upload all the time during a month, I'm not even sure you will be able to exceed the limit.
Check your VPS plan details from their website or look into the email you received after activating your server or into the VPS dashboard. If there is no details reg bandwidth in them, you may have to ask support and wait for them to respond.