How could I correct the "solve" function?

I want to get the answer with solve function.

if I use while loop below, MATLAB returns the empty syms 0-by-1.

E = 6.00;
syms x;

%% all the variables value is assigned %%

while E >= 2.00
    eq = E == E_eq + (R*T)/F*log((1-x)/x) + (R*T)/F*g*(0.5 - x);
    
    theta = vpasolve(eq,x, [-inf inf]);
    
    data_plot = [data_plot; E, theta];
    
    E = E - 0.01;
end

on the other hands,

if I use this loop, it shows the answer but only in a tiny range.

while E >= 2.00
    eq = E == E_eq + (R*T)/F*log((1-x)/x); %% I just delete the "(R*T)/F*g*(0.5 - x)" term.
    
    theta = vpasolve(eq,x, [-inf inf]);
    
    data_plot = [data_plot; E, theta];
    
    E = E - 0.01;
end

when I calculate same function with wolfram alpha, it shows the answer around 3E-34.

is there any way to get the answer under the value 1E-35?

or, do I wrong with using solve function?

[Bjorn Gustavsson]

Renormalize your equation, that is change "units", such that your solution is not so close to the finite precision smalles non-zero number.