Try installing any of these forge versions:
https://aternos.org/software/v/forge/1.12.2-14.23.4.2766
https://aternos.org/software/v/forge/1.12.2-recommended
I tried all of these it didnt work
It says that 1.12.2(14.23.5.2846) is needed
Learn more about this change here.
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