Can't send and receive texts at times.

[Android Central Question]

Also used to have Read and Delivered Option on my texts. Now that is gone. Sometimes when I have to send texts I have to have my WiFi on. I have gone to Sprint twice, spoken to tech twice, and they want me to spend 250 deductible on a 4 month old phone which is ridiculous.

I have a Galaxy Note 8

Any help would be appreciated.
Mario