# How to make the plots update when I adjust parameter in Manipulate?

The plots do not update when I adjust the parameter 'b'. Here is my code:

Manipulate[
sol = NDSolve[{V'[t]*Exp[1/V[t]]*0.2 == Cosh[T[t]/120/V[t]/b] - 1/3,
T'[t]/120 + 2*Exp[-1/V[t]]*Sinh[T[t]] == 0.000002, V[0] == 0.01,
T[0] == 0}, {V[t], T[t]}, {t, 0, 2000000}],
Column[{Plot[{V[t]} /. sol, {t, 0, 2000000}, PlotRange -> All,
PlotLegends -> Automatic],
Plot[{T[t]} /. sol, {t, 0, 2000000}, PlotRange -> All,
PlotLegends -> Automatic]}], {b, 0.5, 1, 0.1}]

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The form of Manipulate is

Manipulate[
code;
code;
final_result (*what will get displayed*)
,  (* notice this is a COMMA *)
control_variable,
control_variable,
other_options
]


Notice, you need ; to separate code in the body of Manipulate up to the final result that will be what is displayed followed by commas after that.

Manipulate[
sol = NDSolve[{V'[t]*Exp[1/V[t]]*0.2 == Cosh[T[t]/120/V[t]/b] - 1/3,
T'[t]/120 + 2*Exp[-1/V[t]]*Sinh[T[t]] == 0.000002, V[0] == 0.01,
T[0] == 0},
{V[t], T[t]}, {t, 0, 2000000}
];
Column[{Plot[{V[t]} /. sol, {t, 0, 2000000}, PlotRange -> All,
PlotLegends -> Automatic],
Plot[{T[t]} /. sol, {t, 0, 2000000}, PlotRange -> All,
PlotLegends -> Automatic]}]
,
{b, 0.5, 1, 0.1}
, TrackedSymbols :> {b}]