blockchain, token, smart contract, solidity

i need to fork (change old brand variable.)
https://bscscan.com/address/0x7f4f3BC4A5634454398580b9112b7E493E2129Fa#code

I need to modify a smart contract bep20 in solidy for disable the sell of token when the marketcap or price fall under 5% of the market cap or price and reactivated after the marketcap or price recovered the 5 %.

example
you start at 0$
and in hight 1$
the marketcap or price decrease
for 5%
so here the marketcap or price is 0,95$
at this marketcap or price the sell is disable
you need to rebuy the dip until 1$
when we have recovered the 5%
the sell is enable

I need you for fix this problem.

you can see you can see the diagram attached