TXT - 365 didn't detect the added TXT record for SPF

It could be a propagation issue OR you have already an existing TXT record in the zone for the same name. Wait up to 48 hours and or check with DNS propagation checkers out there. if you have another TXT record already, just modify the old TXT and add a new line for your TXT value. The DNS propagation checkers also with return the value of the TXT it gets from your name servers.