Update README.md

1ucian0 · web-flow · commit c6a9e767dab3 · 2025-02-26T10:47:41.000+01:00
diff --git a/README.md b/README.md
@@ -12,6 +12,13 @@
   [![License](https://img.shields.io/github/license/qiskit-community/prototype-zne?label=License)](LICENSE.txt)
 
 </div>
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+---
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+⚠️ **Warning:** `prototype-zne` is currently **not maintained**. Use at your own risk.
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+---
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 <!-- PROJECT LOGO -->
 <br />
 <p align="center">
