so you are saying both emails went to rmh-media.com but only one arrived?

We spend some time for further investigation. Enclosed a log file with the full email address of the user. He does not get any mail nor calendar invite if someone uses his Calendso Page. For any further users it’s working. Our IT guys have another issue, maybe the cause. We are with cal since “calendso”. They told me having an issue with the git as well:

calendso@calendso1:~/calendso$ git pull
remote: Enumerating objects: 1651, done.
remote: Counting objects: 100% (1592/1592), done.
remote: Compressing objects: 100% (817/817), done.
remote: Total 1651 (delta 898), reused 1200 (delta 678), pack-reused 59
Receiving objects: 100% (1651/1651), 781.33 KiB | 4.85 MiB/s, done.
Resolving deltas: 100% (899/899), completed with 136 local objects.
From <https://github.com/calcom/cal.com>
   2194b92f..cefd0cfb  main                                           -> origin/main
   8bf3562b..caca045c  admin/team-billing-downgrader                  -> origin/admin/team-billing-downgrader
 * [new branch]        bugfix/undefined-location-in-event-rescheduled -> origin/bugfix/undefined-location-in-event-rescheduled
 * [new branch]        enable-hard-mode                               -> origin/enable-hard-mode
 * [new branch]        feat/conferencing-improvement                  -> origin/feat/conferencing-improvement
 * [new branch]        feat/payment-integration                       -> origin/feat/payment-integration
 + 82741b99...d58b279f feature/team-webhooks                          -> origin/feature/team-webhooks  (forced update)
 * [new branch]        fix/upgrade-trpc                               -> origin/fix/upgrade-trpc
 + db6d7002...93a6039c monorepo/app-store                             -> origin/monorepo/app-store  (forced update)
 + b3b316a6...cf9031b5 staging                                        -> origin/staging  (forced update)
 * [new branch]        tweak/gitignore-prisma-zod                     -> origin/tweak/gitignore-prisma-zod
Updating 2194b92f..cefd0cfb
error: Your local changes to the following files would be overwritten by merge:
	packages/prisma/zod/attendee.ts
	packages/prisma/zod/availability.ts
	packages/prisma/zod/booking.ts
	packages/prisma/zod/bookingreference.ts
	packages/prisma/zod/credential.ts
	packages/prisma/zod/dailyeventreference.ts
	packages/prisma/zod/destinationcalendar.ts
	packages/prisma/zod/eventtype.ts
	packages/prisma/zod/eventtypecustominput.ts
	packages/prisma/zod/index.ts
	packages/prisma/zod/membership.ts
	packages/prisma/zod/payment.ts
	packages/prisma/zod/remindermail.ts
	packages/prisma/zod/resetpasswordrequest.ts
	packages/prisma/zod/schedule.ts
	packages/prisma/zod/selectedcalendar.ts
	packages/prisma/zod/team.ts
	packages/prisma/zod/user.ts
	packages/prisma/zod/verificationrequest.ts
	packages/prisma/zod/webhook.ts
Please commit your changes or stash them before you merge.
Aborting

Can we perform a fresh install and then insert or db backup to keep all users, settings and appointments?