We run TikTok ads to our main site (hosted separately from Mews) and use the Mews Booking Engine embedded via iframe, with the confirmation page loading inside app.mews.com.
TikTok Pixel events (including Purchase) fire correctly and are recorded in TikTok Events Manager, but they don't get credited back to the ad campaigns that drove the click. The root cause seems to be that TikTok's click ID (ttclid) and its first-party cookie (_ttp) are scoped to our domain, and don't carry over once the visitor moves into the Mews iframe on app.mews.com for checkout. Since the confirmation/Purchase event fires inside that iframe, TikTok has no way to tie it back to the original ad click.
Has anyone else running TikTok ads (or a similar third-party pixel with click-ID-based attribution) with Mews hit this same gap? Has anyone found a solution to this ?