How do I reallocate memory for texting feature on a Note 4 in Android version 5.1.1?

[AC Question]

My phone automatically updated to Android version 5.1.1, and now my text feature completely locks up with one contact. The texting works with other contacts, and it worked fine before the upgrade, so how so I allocate enough system memory for this not to lock up?

 

[ManiacJoe]

What leads you to believe the problem is related to memory space?