Is there need for messengers in DnD 5e, if spell Sending exists?

In my campaign (DnD 5e) I would like to send players on a quest to save a kidnapped person. The person has high value information. He/she was ambushed and taken prisoner.

My question is: is there a logical reason for sending a person to deliver a message instead of using 3rd level spell Sending? The spell has no range limitations, and message can be up to 25 words long. What are good reasons for not using a spell? The sender and the receiver would both have resources to hire a Wizard, Bard or Cleric to cast spell, so not using the spell option should be more complex than just “Caster is not available”. In addition the length of a message is less than 25 words.

I would like to keep the idea of sending party on a rescue mission, just need a logical reason for doing so.

How do I turn off Messenger’s default browser?

About a month ago, Messenger implemented an in-app browser, similar to the one on the main Facebook app. It’s terribly slow, and I’d love to load links in Chrome (or Tumblr, or Twitter, or whatever app is actually meant for the link). I’ve looked all over and cannot figure out how to disable it – all help I find is for Facebook’s in-app browser, not Messenger’s. I’m using a Oneplus 3 with the default Oxygen OS. Thanks!