Roblox logon problem on Xbox one (error code 901)?

When I logged in to Roblox it said that there was an error communicating to the Roblox servers and now I want to know how to fix it and is that the case with the other Roblox players?

Many in Germany have just the problem.

I can't PC on roblox and on cell phone either it can't connect so just wait a bit until server go again.

OK thanks