Why are old texts that had been deleted back on my phone? (Samsung Galaxy S6)

[LydSul]

I had some old texts from December I deleted, but when I looked again they were all back on my phone. How can I permanently delete the texts, and what is the fastest way to do so?

 

[Almeuit]

Try using a 3rd party app (like ChompSMS) to remove them. The stock one sometimes can't handle large message deletions.