Hi Arcania,
Thanks for contacting Syncfusion support.
We checked your query and provided information, Based on that we have prepared a Hierarchical Grid sample and checked your reported issue at our end, but we are not able to reproduce the reported issue and Hierarchical Grid with collapse/expand width is working properly at our end. For your convenience we have attached the sample and screenshot representation so please refer the below picture representation and sample for your reference,
Sample: https://stackblitz.com/edit/akfvzl?file=index.js
Online Demo: https://ej2.syncfusion.com/javascript/demos/#/material/grid/hierarchy.html
Screenshot:
So please share us the below information that will be helpful to validate further on this,
1) Share your complete Grid rendering code.
2) Syncfusion package version used.
3) Did you do any customization in the reported Grid?
4) Let us know the replication procedure for reproducing the problem.
5) If possible share us a simple sample to replicate the problem or try reproducing it in the above provided sample.
Please get back to us with the requested details which will be helpful for us to validate the reported issue at our end and provide solution as early as possible
Regards,
Praveenkumar G