GST issue in sales Return of Non Contact Thermometer

Dear Member,

I have quarry regarding the sales Return of Non Contact Thermometer, Earlier GST rate was 18% before 14th July, and we have make bill @ 18% not one dealer has done return aftre 14th july and asking that why 18% gst has been charged in Retunrn, as per new notification GST Rate will be 5%.

My issue is that if sales bill was done in 18% then Return will happen in 18% GST or 5%.

please help me