Error when executing bundle exec jekyll

[5wnUinZa5VUp]

hello,
thank you for publishing
can you help with the following error?

mike@atlantacity:~/Projects/my_blog_test/02.frisco-jekyll-template$ bundle exec jekyll serve --incremental
Configuration file: /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_config.yml
            Source: /home/mike/Projects/my_blog_test/02.frisco-jekyll-template
       Destination: /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_site
 Incremental build: enabled
      Generating... 
Error reading file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_layouts/archive.html: no implicit conversion of Hash into Integer 
Error reading file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_layouts/default.html: no implicit conversion of Hash into Integer 
Error reading file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_layouts/page.html: no implicit conversion of Hash into Integer 
Error reading file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_layouts/post.html: no implicit conversion of Hash into Integer 
             Error: could not read file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_posts/2016-07-20-what-is-a-friend.md: no implicit conversion of Hash into Integer
             Error: could not read file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_posts/2016-07-28-psychology-of-friendship.md: no implicit conversion of Hash into Integer
             Error: could not read file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_posts/2016-08-02-life-cycle.md: no implicit conversion of Hash into Integer
             Error: could not read file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_posts/2016-08-06-development-issues.md: no implicit conversion of Hash into Integer
             Error: could not read file /home/mike/Projects/my_blog_test/02.frisco-jekyll-template/_posts/2016-08-12-health.md: no implicit conversion of Hash into Integer
jekyll 3.8.4 | Error:  undefined method `valid_encoding?' for nil:NilClass

          if doc.content.valid_encoding?
                        ^^^^^^^^^^^^^^^^
/home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/readers/post_reader.rb:39:in `block in read_publishable': undefined method `valid_encoding?' for nil:NilClass (NoMethodError)

          if doc.content.valid_encoding?
                        ^^^^^^^^^^^^^^^^
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/readers/post_reader.rb:38:in `select'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/readers/post_reader.rb:38:in `read_publishable'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/readers/post_reader.rb:27:in `read_posts'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/reader.rb:64:in `retrieve_posts'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/reader.rb:50:in `read_directories'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/reader.rb:16:in `read'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/site.rb:164:in `read'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/site.rb:69:in `process'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/command.rb:28:in `process_site'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/commands/build.rb:65:in `build'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/commands/build.rb:36:in `process'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/commands/serve.rb:93:in `block in start'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/commands/serve.rb:93:in `each'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/commands/serve.rb:93:in `start'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/lib/jekyll/commands/serve.rb:75:in `block (2 levels) in init_with_program'
        from /home/mike/.gem/ruby/3.1.0/gems/mercenary-0.3.6/lib/mercenary/command.rb:220:in `block in execute'
        from /home/mike/.gem/ruby/3.1.0/gems/mercenary-0.3.6/lib/mercenary/command.rb:220:in `each'
        from /home/mike/.gem/ruby/3.1.0/gems/mercenary-0.3.6/lib/mercenary/command.rb:220:in `execute'
        from /home/mike/.gem/ruby/3.1.0/gems/mercenary-0.3.6/lib/mercenary/program.rb:42:in `go'
        from /home/mike/.gem/ruby/3.1.0/gems/mercenary-0.3.6/lib/mercenary.rb:19:in `program'
        from /home/mike/.gem/ruby/3.1.0/gems/jekyll-3.8.4/exe/jekyll:15:in `<top (required)>'
        from /home/mike/.gem/ruby/3.1.0/bin/jekyll:25:in `load'
        from /home/mike/.gem/ruby/3.1.0/bin/jekyll:25:in `<main>'

bundle version:

mike@atlantacity:~/Projects/my_blog_test/02.frisco-jekyll-template$ bundle -v
Bundler version 2.4.22