Cannot Connect to Running Lightsail Instance after taking Snapshot

Hi,

As stated in the title - Last week I took 2 snapshots of my instance (both a regular one and then a Sysprep one) as we are planning to upgrade to a new instance. However, now when I try to access my instance, even though it says it is running and I have tried restarting numerous times, I cannot connect. Accessing through a web browser just brings up a blank screen, and trying to access through RDP gives the error:

Session Ended.

You have been disconnected because another connection was made to the remote PC.

Error code: 0x516

Extended error code: 0x0

Activity ID: {3c41404e-e8bc-4449-bcdb-542c6aa60000}

Have I erred in creating the sysprep snapshot? I assumed that was just a backup but it seems like I have to just go ahead and get the new instance running before I can do anything.