Newton-Raphson algorithm stuck running after 4 or 5 iterations

Code:   %% initial setup syms x real f = x^5-2*x^3+4*x+2; error_lim = 1e-5; %% newton raphson d_f = diff(f); m = 5; disp(m) % iterate till root is found with certain accuracy more off; while true e = m - subs(f,m)/subs(d_f,m); err = abs(e-m); fprintf("error = %g\n", err) if err < error_lim break end m = e; fprintf("x_p = %g\n", m) end fprintf("the root newton raphson method is %g\n", e) and the output is: >> stat3_b 5 error = 0.972474 x_p = 4.02753 error = 0.774926 x_p = 3.2526 error = 0.620288 x_p = 2.63231 error = 0.505877 x_p = 2.12643 error = 0.439351 x_p = 1.68708 error = 0.467107 x_p = 1.21998 error = 0.968289 x_p = 0.251687 error = 0.817551 x_p = -0.565863 After 8th iterations matlab is busy, but nothing prints. It runs and gives appropriate solution of the function when initial m is set to 1 or 2 but problem arises when m is set to 3 or higher. What is wrong with the above allgorithm?