@Mahalakshmi Thanks for reaching out to us, your every train will create a new custom model which you can rename, and you can delete the old one you don't need.
To retrain a model, you can leverage the "Run layout" button on the left top to import the old model and change the labels.
You are almost on the right way, then you can test the model then retrain it if the result is not perfect as you expect. Please make sure when you retrain, the version is the correct version.
Please take a look at the life cycle of the model.
I hope this helps.
Regards,
Yutong
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