Mac won't update
My MacOS Catalina
Version 10.15.7
MacBook Pro (13-inch, Mid 2012)
Processor 2.5 GHz Dual-Core Inter Core i5
Memory 4GB 1600 MHz DDR3
Graphics Intel HD Graphics 4000 1536 MB
I have been trying to update my computer but it isn't allowing me too update and I was wondering what I could do about it?
MacBook Pro 13″, macOS 10.15