Why does Git add a backend but not a frontend?

Question

git

Don't hit hard, I don't know Git well, this is my first project with it.
I broke my head why Git adds a backend to the repository (on Laravel 5.4), but does not add a frontend (on Angular 5.2).
The project structure is as follows:

drwxrwxr-x  6 noname noname   4096 мар 20  2018 ./
drwxrwxr-x 11 noname www-data 4096 ноя 15 21:57 ../
drwxrwxr-x 14 noname noname   4096 мар 14  2018 backend/
drwxrwxr-x  5 noname noname   4096 авг 15 21:50 frontend/
drwxrwxr-x  8 noname noname   4096 ноя 27 16:38 .git/
drwxrwxr-x  3 noname noname   4096 окт 31 14:26 .idea/

Tried different things:

git add .
git add . —force
git add frontend
git add frontend/*
git add —all
git add :/

...but the frontend folder, unlike backend, is completely ignored.
Gitignore is only available in the backend dir:

./backend/vendor/sebastian/global-state/.gitignore
./backend/vendor/sebastian/object-enumerator/.gitignore
./backend/vendor/sebastian/comparator/.gitignore
./backend/vendor/sebastian/exporter/.gitignore
./backend/vendor/sebastian/diff/.gitignore
./backend/vendor/sebastian/environment/.gitignore
./backend/vendor/sebastian/recursion-context/.gitignore
./backend/vendor/sebastian/resource-operations/.gitignore
./backend/vendor/sebastian/code-unit-reverse-lookup/.gitignore
./backend/vendor/sebastian/version/.gitignore
./backend/vendor/dnoegel/php-xdg-base-dir/.gitignore
./backend/vendor/nikic/php-parser/.gitignore
./backend/vendor/jakub-onderka/php-console-highlighter/.gitignore
./backend/vendor/jakub-onderka/php-console-color/.gitignore
./backend/vendor/symfony/routing/.gitignore
./backend/vendor/symfony/yaml/.gitignore
./backend/vendor/symfony/var-dumper/.gitignore
./backend/vendor/symfony/translation/.gitignore
./backend/vendor/symfony/console/.gitignore
./backend/vendor/symfony/debug/.gitignore
./backend/vendor/symfony/finder/.gitignore
./backend/vendor/symfony/process/.gitignore
./backend/vendor/symfony/event-dispatcher/.gitignore
./backend/vendor/symfony/http-foundation/.gitignore
./backend/vendor/symfony/css-selector/.gitignore
./backend/vendor/symfony/http-kernel/.gitignore
./backend/vendor/tymon/jwt-auth/.gitignore
./backend/vendor/phpunit/php-code-coverage/.gitignore
./backend/vendor/phpunit/php-token-stream/.gitignore
./backend/vendor/phpunit/php-file-iterator/.gitignore
./backend/vendor/phpunit/phpunit/.gitignore
./backend/vendor/phpunit/php-text-template/.gitignore
./backend/vendor/phpunit/phpunit-mock-objects/.gitignore
./backend/vendor/phpunit/php-timer/.gitignore
./backend/vendor/myclabs/deep-copy/.gitignore
./backend/vendor/doctrine/instantiator/.gitignore
./backend/vendor/mockery/mockery/docs/.gitignore
./backend/vendor/mockery/mockery/.gitignore
./backend/vendor/namshi/jose/.gitignore
./backend/vendor/hamcrest/hamcrest-php/.gitignore
./backend/vendor/fzaninotto/faker/.gitignore
./backend/vendor/psr/log/.gitignore
./backend/vendor/swiftmailer/swiftmailer/.gitignore
./backend/vendor/psy/psysh/.gitignore
./backend/bootstrap/cache/.gitignore
./backend/database/.gitignore
./backend/storage/logs/.gitignore
./backend/storage/framework/cache/.gitignore
./backend/storage/framework/.gitignore
./backend/storage/framework/views/.gitignore
./backend/storage/framework/sessions/.gitignore
./backend/storage/framework/testing/.gitignore
./backend/storage/app/public/.gitignore
./backend/storage/app/.gitignore

Frontend has a standard structure for Angular:

drwxrwxr-x   5 noname noname   4096 авг 15 21:50 ./
drwxrwxr-x   6 noname noname   4096 мар 20  2018 ../
-rw-rw-r--   1 noname noname   1243 мар 15  2018 .angular-cli.json
drwxrwxr-x   2 noname noname   4096 мар 15  2018 e2e/
-rw-rw-r--   1 noname noname    245 мар 15  2018 .editorconfig
-rw-rw-r--   1 noname noname    923 мар 15  2018 karma.conf.js
drwxrwxr-x 890 noname noname 122880 мар 15  2018 node_modules/
-rw-rw-r--   1 noname noname   1293 мар 15  2018 package.json
-rw-rw-r--   1 noname noname 423951 мар 15  2018 package-lock.json
-rw-rw-r--   1 noname noname    722 мар 15  2018 protractor.conf.js
-rw-rw-r--   1 noname noname   1024 мар 15  2018 README.md
drwxrwxr-x   5 noname noname   4096 мар 15  2018 src/
-rw-rw-r--   1 noname noname    363 мар 15  2018 tsconfig.json
-rw-rw-r--   1 noname noname   3012 мар 15  2018 tslint.json

The index contains only the Frontend folder itself, but there are no contents...

[email protected]:~/projects/dev_prop$ git ls-files
backend/app/Console/Commands/Moderated.php
backend/app/Console/Kernel.php
...
frontend

I will add that earlier there was my own .git in the Frontend folder, I demolished it, because. this is what could prevent the appearance of the Frontend folder in the repository.
Tell me what could be the matter?

Answer 1

I will answer myself as I got out of the situation, suddenly it will be useful to someone.
It was not possible to find the reason for not adding the frontend. As a result, I decided to create separate repositories for the backend and frontend. And the problem was thus solved.