Hi @PAWAN CHETTRI ,
There are three types of FormMode in Power Apps:
If you choose "Edit" mode, it will update the record to data source.So for your issue, please check whether DefaultMode is set to “Edit”:
You can click your Form in the Tree view -> Select “DefaultMode” from the drop-down list on the top -> check if the mode is “Edit” :
If it is not, change it to “Edit” and retry.
Besides,as your issue is more related to Power Apps, I suggest you to go to Power Apps Community for better help.
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