What firmware running on your GDS3710?
If it is latest version 220.127.116.11, have you tried configure the “Keep Door Open” feature? (Default is disabled).
You can configure the GDS3710 controlling the strike by either “Immediately Open Door” or “Schedule Open Door”, and configure the time span or length to keep the door open. You can also program “Emergency PIN to Disable Keep Door Open” to overlap the open door (locking the door when it is open status) from GDS3710 keypad, or from the webUI by logging into the GDS3710.
This feature is designed for application scene like Schools, Library, Government, Clubs, Gyms, etc., where in some specific time the place will open to public and door is unlocked but will be locked at other times and employees can use PIN or RFIC to get in while locked. Also the staff can overwrite the open door setting by locking the door immediately in the keypad of GDS3710 by entering emergency PIN. (like for example, in the morning the school door is open allowing students and parents getting in, but if something happened, any staff knowing the emergency PIN can access to the door by input the emergency PIN to change the door from OPEN to LOCK, or from computer logging into the webUI of GDS3710 to do that.
Hope this helps. Feel free to contact me or Grandstream Support if you have further questions.
Thank you for using GDS3710!