Updating Subform Record from other Form

Updating Subform Record from other Form

Just wanted to ask how to properly approach this. I have 2 forms and would like to trigger an auto update on the subform once record submitted.
block below only updates 1 row
for each  recordRow in input.AV_System
{
AssetRecord = Site_Asset_Services[SOR_No == input.SOR2 && Type_of_System == "AV System" && Site_Asset.Serial_N == recordRow.AV_Serial_N].Site_Asset;
for each  rec in AssetRecord
{
AssetRecord.Floor=recordRow.AV_Floor;
AssetRecord.Room_Name=recordRow.AV_Room_Name;
AssetRecord.Brand=recordRow.AV_Brand;
AssetRecord.Model=recordRow.AV_Model;
AssetRecord.Serial_N=recordRow.AV_Serial_N;
AssetRecord.Description=recordRow.AV_Description;
AssetRecord.Status=recordRow.AV_Status;
AssetRecord.Remarks=recordRow.AV_Remarks;
}
}

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