After migration from Expand to PA a domain resolves to two IP addresses, despite the DNS service is not yet switched to PA on the registrar side.
DNS zones hosted on current DNS servers was updated as a result of migration.
Top > Service Director > Domain Manager > Domains > example.com > DNS Zone there are two sets of DNS records mixed up, for instance
example.com. 600 A 126.96.36.199 example.com. 600 A 188.8.131.52
That is why 2 IP addresses are returned.
Switch to the DNS Records suppliers tab and you will see that DNS records are taken from both PA and Plesk subscriptions at the same time.
To correct DNS information, please go
Top > Service Director > Domain Manager > Domains > example.com, press Edit and leave only one subscription in the Used by subscriptions list.