diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index fbda584..e8e6d99 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -4,7 +4,7 @@
 2. [Create a topic branch.][branch]
 3. Implement your feature or bug fix.
 4. Don't forget to add specs and make sure they pass by running `rspec .`.
-5. Make sure your code complies with the style guide by running `rubocop`. `rubocop -a` can automatically fix most issues for you.
+5. Make sure your code complies with the style guide by running `rubocop`. `rubocop -a` can automatically fix most issues for you. Run `rubocop -A` to make it more aggressive.
 6. If necessary, add documentation for your feature or bug fix.
 7. Commit and push your changes.
 8. [Submit a pull request.][pr]
diff --git a/.travis.yml b/.travis.yml
index d4a0cfb..17f168d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,9 @@
 language: ruby
 
 rvm:
-- 2.6.7
-- 2.7.3
-- 3.0.1
+- 2.6.8
+- 2.7.4
+- 3.0.2
 
 install: bundle install --retry=3
 
diff --git a/docs/Gemfile b/docs/Gemfile
index e96e8ce..0805e4f 100644
--- a/docs/Gemfile
+++ b/docs/Gemfile
@@ -17,7 +17,7 @@ gem 'minima', '~> 2.0'
 
 # If you want to use GitHub Pages, remove the "gem "jekyll"" above and
 # uncomment the line below. To upgrade, run `bundle update github-pages`.
-gem 'github-pages', '~> 218', group: :jekyll_plugins
+gem 'github-pages', '~> 219', group: :jekyll_plugins
 
 # If you have any plugins, put them here!
 group :jekyll_plugins do
diff --git a/docs/additional_info/changelog.md b/docs/additional_info/changelog.md
index 44f9198..141f04a 100644
--- a/docs/additional_info/changelog.md
+++ b/docs/additional_info/changelog.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## 4.3.1 (21-Sep-21)
+
+* Make exception handling more solid
+* Test with more recent Rubies
+
 ## 4.3.0 (15-Jul-21)
 
 * Added support for GZip compression. It is off by default but you can enable it by setting the `enable_compression` option to `true`:
diff --git a/lib/ruby-lokalise-api/error.rb b/lib/ruby-lokalise-api/error.rb
index b7fa596..92c2578 100644
--- a/lib/ruby-lokalise-api/error.rb
+++ b/lib/ruby-lokalise-api/error.rb
@@ -39,7 +39,8 @@ class Error < StandardError
     class << self
       # Create a new error from an HTTP response
       def from_response(body)
-        new body['error']['message'].to_s
+        msg = body.key?('error') ? body['error']['message'] : body['message']
+        new msg.to_s
       end
     end
 
diff --git a/lib/ruby-lokalise-api/request.rb b/lib/ruby-lokalise-api/request.rb
index d22040b..6088e54 100644
--- a/lib/ruby-lokalise-api/request.rb
+++ b/lib/ruby-lokalise-api/request.rb
@@ -58,7 +58,7 @@ def prepare(path)
     def respond_with(response, client)
       body = custom_load response.body
       uri = Addressable::URI.parse response.env.url
-      respond_with_error(response.status, body) if body.respond_to?(:has_key?) && body.key?('error')
+      respond_with_error response.status, body if response.status.between?(400, 599) || (body.respond_to?(:has_key?) && body.key?('error'))
       extract_headers_from(response).
         merge('content' => body,
               'client' => client,
@@ -74,7 +74,7 @@ def extract_headers_from(response)
     end
 
     def respond_with_error(code, body)
-      raise(Lokalise::Error, body['error']) unless Lokalise::Error::ERRORS.key? code
+      raise(Lokalise::Error, body['error'] || body) unless Lokalise::Error::ERRORS.key? code
 
       raise Lokalise::Error::ERRORS[code].from_response(body)
     end
diff --git a/lib/ruby-lokalise-api/version.rb b/lib/ruby-lokalise-api/version.rb
index 61caf41..2de8e7e 100644
--- a/lib/ruby-lokalise-api/version.rb
+++ b/lib/ruby-lokalise-api/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Lokalise
-  VERSION = '4.3.0'
+  VERSION = '4.3.1'
 end
diff --git a/spec/fixtures/vcr_cassettes/error_no_error_key.yml b/spec/fixtures/vcr_cassettes/error_no_error_key.yml
new file mode 100644
index 0000000..c633a46
--- /dev/null
+++ b/spec/fixtures/vcr_cassettes/error_no_error_key.yml
@@ -0,0 +1,51 @@
+---
+http_interactions:
+- request:
+    method: get
+    uri: https://api.lokalise.com/api2/projects
+    body:
+      encoding: US-ASCII
+      string: ''
+    headers:
+      Accept:
+      - application/json
+      User-Agent:
+      - ruby-lokalise-api gem/4.3.0
+      X-api-token:
+      - invalid
+  response:
+    status:
+      code: 400
+      message: Bad Request
+    headers:
+      server:
+      - nginx
+      date:
+      - Tue, 21 Sep 2021 12:26:16 GMT
+      content-type:
+      - application/json
+      transfer-encoding:
+      - chunked
+      connection:
+      - keep-alive
+      cache-control:
+      - max-age=0, must-revalidate, no-cache, no-store, private
+      pragma:
+      - no-cache
+      x-content-type-options:
+      - nosniff
+      x-frame-options:
+      - deny
+      x-xss-protection:
+      - 1; mode=block
+      strict-transport-security:
+      - max-age=31536000
+      referrer-policy:
+      - origin
+      expires:
+      - Tue, 21 Sep 2021 12:26:16 GMT
+    body:
+      encoding: UTF-8
+      string: '{"message":"Invalid `X-Api-Token` header","code":400}'
+  recorded_at: Tue, 21 Sep 2021 12:26:16 GMT
+recorded_with: VCR 6.0.0
diff --git a/spec/lib/ruby-lokalise-api/error_spec.rb b/spec/lib/ruby-lokalise-api/error_spec.rb
index ba4958d..db0e3d3 100644
--- a/spec/lib/ruby-lokalise-api/error_spec.rb
+++ b/spec/lib/ruby-lokalise-api/error_spec.rb
@@ -15,6 +15,14 @@
     end.to raise_error(described_class)
   end
 
+  it 'handles an exception when the response does not contain an error key' do
+    expect do
+      VCR.use_cassette('error_no_error_key') do
+        get 'projects', Lokalise.client('invalid')
+      end
+    end.to raise_error(Lokalise::Error::BadRequest)
+  end
+
   it 'raises BadRequest when API token is invalid' do
     expect do
       VCR.use_cassette('error_invalid_token') do