Issue with Docker Build and source file specification syntax

I am trying to recreate a simple container detailed here: https://github.com/zaproxy/community-scripts/blob/master/api/mass-baseline/docker-wrapper

The wrapper code is below:

FROM owasp/zap2docker-weekly
**MAINTAINER Simon Bennets

USER zap
COPY mass-base* /zap/
RUN mkdir /zap/wrk
COPY mass-baseline-default.conf /zap/wrk/mass-baseline-default.conf

USER root
RUN chown zap /zap/mass-base*

But each time I execute docker -> build using this file, I get an error about source files not being available.

Step 1/8 : FROM owasp/zap2docker-weekly
—> f309e7451935
Step 2/8 : MAINTAINER Simon Bennetts
—> Using cache
—> db1beffafccb
Step 3/8 : USER zap
—> Using cache
—> 136bfa98764a
Step 4/8 : COPY mass-base /zap/*
COPY failed: no source files were specified

Is there an issue with my syntax in step 4 that I am simply not seeing? I believe the wildcard after mass-base should suffice for copying all files with that beginning naming convention, but clearly this is not the case. Thanks in advance for any help!

Running Docker v. 18.09.6 on RHEL 7