Opt-in problems

My new member does not seem to be receiving the opt-in email. I have double-checked the email address I used and asked him to check his junk folder, but he is not receiving it. What do you think could be the problem?
Thanks for your help.
Kate McClare
Club #2798

The system has sent him 3 emails, have him add Server@toastmastersclubs.org and agenda@toastmasters.org to his email safe list.

Mar 23 23:02:04 toastmastersclubs sendmail[19215]: 52NN22Gs019212: to=<saperret@bontrade.com>, ctladdr= (501/502), delay=00:00:02, xdelay=00:00:02, mailer=esmtp, pri=122198, relay=bontrade-com.mail....ction.outlook.com. [52.101.42.13], dsn=2.0.0, stat=Sent (<202503232302.52NN22Gs019212@toastmastersclubs.org> [InternalId=3998614552990, Hostname=IA0PPF88AEDEFB9.namprd15.prod.outlook.com] 13649 bytes in 0.303, 43.939 KB/sec Queued mail for delivery)

Mar 23 23:03:08 toastmastersclubs sendmail[19853]: 52NN36Wa019850: to=<saperret@bontrade.com>, ctladdr= (501/502), delay=00:00:02, xdelay=00:00:02, mailer=esmtp, pri=122198, relay=bontrade-com.mail....ction.outlook.com. [52.101.41.58], dsn=2.0.0, stat=Sent (<202503232303.52NN36Wa019850@toastmastersclubs.org> [InternalId=35884451758473, Hostname=SA1PR15MB5799.namprd15.prod.outlook.com] 13636 bytes in 0.203, 65.360 KB/sec Queued mail for delivery)

Mar 24 02:55:39 toastmastersclubs sendmail[13061]: 52O2tbOr013057: to=<saperret@bontrade.com>, ctladdr= (501/502), delay=00:00:02, xdelay=00:00:02, mailer=esmtp, pri=122198, relay=bontrade-com.mail....ction.outlook.com. [52.101.41.6], dsn=2.0.0, stat=Sent (<202503240255.52O2tbOr013057@toastmastersclubs.org> [InternalId=154472793773409, Hostname=PH0PR15MB4687.namprd15.prod.outlook.com] 13681 bytes in 0.121, 110.253 KB/sec Queued mail for delivery)