fix: validation for membership
diff --git a/erpnext/non_profit/doctype/membership/membership.py b/erpnext/non_profit/doctype/membership/membership.py
index 4c85cb6..7d15aba 100644
--- a/erpnext/non_profit/doctype/membership/membership.py
+++ b/erpnext/non_profit/doctype/membership/membership.py
@@ -70,7 +70,7 @@
 		settings = frappe.get_doc("Membership Settings")
 
 		if not member.customer:
-			frappe.throw(_("No customer linked to member {}", [member.name]))
+			frappe.throw(_("No customer linked to member {0}").format(frappe.bold(self.member)))
 
 		if not settings.debit_account:
 			frappe.throw(_("You need to set <b>Debit Account</b> in Membership Settings"))