Problem with dockerhub image

My Docker builds began failing a few days ago with the error messages below. I notice that the image on dockerhub was updated about 4 days ago. Might this be a coincidence? I really don't know how to fix this. Please offer suggestions.

Step 1/16 : FROM pcic/geospatial-python
 ---> 8e26851956b9
Step 2/16 : MAINTAINER Mike McCann <mccann@xxx>
 ---> Using cache
 ---> fa2f1d823f19
Step 3/16 : ENV DEBIAN_FRONTEND noninteractive
 ---> Using cache
 ---> 04906b8a465f
Step 4/16 : RUN apt-get update &&     apt-get -qq -y install     firefox     freetds-dev     git     gmt     imagemagick     libncurses-dev     time     wget     xvfb
 ---> Running in b9b1ce0e5558

Ign:1 http://security.ubuntu.com/ubuntu cosmic-security InRelease
Err:2 http://security.ubuntu.com/ubuntu cosmic-security Release
  404  Not Found [IP: 91.189.91.23 80]
Ign:3 http://archive.ubuntu.com/ubuntu cosmic InRelease
Ign:4 http://archive.ubuntu.com/ubuntu cosmic-updates InRelease
Ign:5 http://archive.ubuntu.com/ubuntu cosmic-backports InRelease
Err:6 http://archive.ubuntu.com/ubuntu cosmic Release
  404  Not Found [IP: 91.189.88.162 80]
Err:7 http://archive.ubuntu.com/ubuntu cosmic-updates Release
  404  Not Found [IP: 91.189.88.162 80]
Err:8 http://archive.ubuntu.com/ubuntu cosmic-backports Release
  404  Not Found [IP: 91.189.88.162 80]
Reading package lists...
E: The repository 'http://security.ubuntu.com/ubuntu cosmic-security Release' does not have a Release file.
E: The repository 'http://archive.ubuntu.com/ubuntu cosmic Release' does not have a Release file.
E: The repository 'http://archive.ubuntu.com/ubuntu cosmic-updates Release' does not have a Release file.
E: The repository 'http://archive.ubuntu.com/ubuntu cosmic-backports Release' does not have a Release file.
ERROR: Service 'stoqs' failed to build: The command '/bin/sh -c apt-get update &&     apt-get -qq -y install     firefox     freetds-dev     git     gmt     imagemagick     libncurses-dev     time     wget     xvfb' returned a non-zero code: 100

Start by inspecting the Dockerfile's FROM pcic/geospatial-python image and the apt-get update step shown in the report, then check whether the Ubuntu cosmic repositories are still available. Done means the image builds successfully and the package installation step no longer returns repository 404 errors.