Thanks for reaching out to us, Hamid. I just need to clarify a few things.
When you mentioned changing the GST type on the invoice page, were you referring to the GST type drop-down menu or the GST rates drop-down menu?

If you're unable to change the GST type or GST rates, I recommend clearing your browser's cache to fix any issues caused by corrupted files. You can also switch to another supported browser for smoother performance.
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