Shanee8126,
Thanks for letting us know. Next, have you tried restarting your device to see if that positively impacts the issue you’re experiencing as it pertains to the Messages app on your iPhone? If not, please try that by following the steps in the link below.
Restart your iPhone - Apple Support
1) Press and hold either volume button and the side button until the power-off slider appears.

2) Drag the slider, then wait 30 seconds for your device to turn off. If your device is frozen or unresponsive, force restart your device.
3) To turn your device back on, press and hold the side button (on the right side of your iPhone) until you see the Apple logo.
We recommend the steps above because while a restart can seem unimportant, it can resolve many minor issues with the device.
Also, use the link below to double-check to make sure that the contact you're referring to hasn't accidentally been blocked.
Block phone numbers, contacts, and emails on your iPhone or iPad - Apple Support
Please let us know the outcome after giving the above steps a try.
Thanks for using the Apple Support Communities.
Cheers!