fix: Patch for updating Appointment Reminder method in Scheduled Job Type (#21431)

diff --git a/erpnext/patches.txt b/erpnext/patches.txt
index eaeebcf..a216f53 100644
--- a/erpnext/patches.txt
+++ b/erpnext/patches.txt
@@ -674,3 +674,4 @@
 erpnext.patches.v12_0.update_end_date_and_status_in_email_campaign
 erpnext.patches.v13_0.move_tax_slabs_from_payroll_period_to_income_tax_slab #123
 erpnext.patches.v12_0.fix_quotation_expired_status
+erpnext.patches.v12_0.update_appointment_reminder_scheduler_entry
\ No newline at end of file
diff --git a/erpnext/patches/v12_0/update_appointment_reminder_scheduler_entry.py b/erpnext/patches/v12_0/update_appointment_reminder_scheduler_entry.py
new file mode 100644
index 0000000..91931ee
--- /dev/null
+++ b/erpnext/patches/v12_0/update_appointment_reminder_scheduler_entry.py
@@ -0,0 +1,7 @@
+import frappe
+
+def execute():
+	job = frappe.db.exists('Scheduled Job Type', 'patient_appointment.send_appointment_reminder')
+	if job:
+		method = 'erpnext.healthcare.doctype.patient_appointment.patient_appointment.send_appointment_reminder'
+		frappe.db.set_value('Scheduled Job Type', job, 'method', method)
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