Dotnet build down

I have log:

C# support for Travis-CI is community maintained.

146Please open any issues at https://travis-ci.community/c/languages/37-category and cc @joshua-anderson @akoeplinger @nterry

147Installing .NET Core
148$ export DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1
149$ export DOTNET_CLI_TELEMETRY_OPTOUT=1
15014.06s0.41sE: Unable to locate package dotnet-sdk-3.1
151E: Couldn't find any package by glob 'dotnet-sdk-3.1'
152E: Couldn't find any package by regex 'dotnet-sdk-3.1'

153The command "sudo apt-get install -qq dotnet-sdk-3.1" failed and exited with 100 during .

It also fails for .net 2.1

Installing .NET Core
$ export DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1
$ export DOTNET_CLI_TELEMETRY_OPTOUT=1
Unable to locate package dotnet-sdk-2.1

Couldn’t find any package by glob ‘dotnet-sdk-2.1’
Couldn’t find any package by regex ‘dotnet-sdk-2.1’
The command “sudo apt-get install -qq dotnet-sdk-2.1” failed and exited with 100 during .

Any suggestions? @joshua-anderson

system_info
Build system information
Build language: csharp
Build group: stable
Build dist: xenial
Build id: 637141760
Job id: 637141761
Runtime kernel version: 4.15.0-1028-gcp
travis-build version: 1c634e1df
Build image provisioning date and time
Mon Mar 25 16:52:50 UTC 2019

Operating System Details
Distributor ID: Ubuntu
Description: Ubuntu 16.04.6 LTS
Release: 16.04
Codename: xenial

Looks like it might be working now