# Why this error keeps appearing even after I inputted using AlgebraOfGraphs and using PlotUtils

**URL:** <https://discourse.pumas.ai/t/why-this-error-keeps-appearing-even-after-i-inputted-using-algebraofgraphs-and-using-plotutils/1439>\
**Category:** Basic Usage\
**Created:** [September 20, 2026, 3:31pm UTC](https://discourse.pumas.ai/t/why-this-error-keeps-appearing-even-after-i-inputted-using-algebraofgraphs-and-using-plotutils/1439 "2026-09-20T15:31:57Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![yjzheng2023](https://avatars.discourse-cdn.com/v4/letter/y/7ba0ec/32.png) [@yjzheng2023](https://discourse.pumas.ai/u/yjzheng2023)\
**Post date:** [September 20, 2026, 3:31pm UTC](https://discourse.pumas.ai/t/why-this-error-keeps-appearing-even-after-i-inputted-using-algebraofgraphs-and-using-plotutils/1439/1 "2026-09-20T15:31:57Z")

</div>

UndefVarError: `Lines` not defined in `Main`  
Suggestion: check for spelling errors or missing imports.  
Hint: a global variable of this name may be made accessible by importing Makie in the current active module Main  
Hint: a global variable of this name may be made accessible by importing CairoMakie in the current active module Main  
Stacktrace:  
[1] top-level scope

---

<div class="post-metadata">

**Author:** ![andreasnoack](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.pumas.ai/andreasnoack/32/22_2.png) [@andreasnoack](https://discourse.pumas.ai/u/andreasnoack)\
**Post date:** [September 21, 2026, 10:20am UTC](https://discourse.pumas.ai/t/why-this-error-keeps-appearing-even-after-i-inputted-using-algebraofgraphs-and-using-plotutils/1439/2 "2026-09-21T10:20:00Z")

</div>

Please explain what you are trying to do and if you tried following the hint in the error message.