are you saying the scopes don't open? I have the same problem with an out of date macbookpro form 2012. It's too old for the scopes to work, otherwise, it's still usable.
how can this be fixed?
Please tell us your system specs: OS version, Premiere version, amount of RAM, Hardware specs including graphics card.
If you're system doesn't meet the minimum specs for premiere 2020
You can try installing 2019 which is still available as far as I know at this moment. As I said, my 2012 macbook pro does not meet the specs for 2020 but the only limitation I've found is that the lumetri scopes do not appear. They do work in 2019.
As an alternative, you can output an xml from premiere and do your color correct in davinci resolve. There is a free version available which has only a few limitations.
MacBook Pro (15-inch, Mid 2012)
2,3 GHz 4‑ядерный процессор Intel Core i7
16 ГБ 1600 MHz DDR3
NVIDIA GeForce GT 650M 512 МБ
Intel HD Graphics 4000 1536 МБ
Yup, that's pretty similar to my machine (except mine's a 13"). So yeah, either work in premiere 2019, work without the scopes in 2020, or send to resolve for color correct.