Hello ygytlykay,
Were these the steps that you had tried already: If you can't send or receive messages on your iPhone or iPad - Apple Support
If not, those steps may be able to help out with issues sending texts.
Are these being sent as iMessages (blue bubble) or SMS/MMS (green bubble)? If it's iMessage, does the red exclamation point show up next to the message? If so, try the following:
If you try to send a message and you see
with an alert that says Not Delivered, follow these steps:
1. Check your network connection.
2. Tap
, then tap Try Again.
3. If you still can’t send the message, tap
, then tap Send as Text Message. Messaging rates may apply. Contact your carrier for more information.
Are you experiencing issues receiving texts from anyone else? Checking on that can help to see if there may be a broader issue.
Be sure to check that their contact card hadn't been inadvertently blocked as well. This page can assist with that: Block phone numbers, contacts, and emails on your iPhone, iPad, or iPod touch - Apple Support
Cheers.