Calendar sync
Reviewers report phantom appointments, conflicting events that slip through, and sync glitches that erode the whole point of automated booking.
What people actually say
✕Calendar sync glitches such as phantom appointments and missed conflicts affect a meaningful share of users — sync issues are a frequent theme in reviews.
Source: G2 — Calendly cons ↗✕The free plan only allows a single connected calendar, so anyone juggling personal + work Google calendars has to upgrade just to stop double-bookings.
Source: Koalendar — Calendly free vs paid ↗✕Support is widely described as unresponsive for billing or technical issues — users frequently fall back to help articles instead of live help when sync breaks.
Source: SchedulingKit — Calendly review 2026 ↗
Direct Google Calendar and Microsoft Graph integrations driven by Inngest workers, with idempotent write retries and a full event audit log in Postgres. Conflicts are checked at the source of truth on every booking — no eventual-consistency phantom slots, and every desk worker can connect as many calendars as they have.