Lawrence Phillips Letter -- Prison Staff Is Messing with Me

Lawrence Phillips complained that prison staffers were screwing with him in the month before he died ... messing with his mail and breaking his TV ... according to a letter penned by the ex-NFL star.

TMZ Sports obtained the letter Phillips sent to his old high school football coach on Dec. 6th -- in which he implied staffers at Kern Valley State Prison were NOT delivering his mail.

"The mail situation is terrible," Phillips wrote.

"Everyone is pointing the finger at everyone else. I surely am not receiving all my mail as well as mail I am sending is not being received. There were two letters you mentioned that I never received. This new attorney has said he is addressing the issue."

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