scipy curve_fit does not fit data; no error is thrown

Question

I am trying to fit my data (see attached picture) using the following function (convolution of a Gaussian with exponential decays). However, the fit is not good no matter what my initial guess is. I'm not sure why? Can anyone help?

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
from scipy.optimize import curve_fit
plt.rcParams["font.size"] = 16
plt.rcParams['figure.figsize'] = (10, 5)

#u is the location (mean) of Gaussian (determines the rise of feature)
#d is FWHM of the Gaussian (determines the width of convolution)

def one_exp_fit_function(t1, d, u, k1):
    d_bar = d/(2*np.sqrt(np.log(2)))
    i = ((d_bar*np.sqrt(2*np.pi))**(-1))*np.exp(-np.log(2)*(((2*(t1-u))/d)**2))
    f = np.exp(-(k1)*t1)
    k = np.convolve(i, f, mode='same')
    return k

p0 = [0.15, 908.1, 0.0029]


popt, pcov = curve_fit(one_exp_fit_function, Time, Intensity, p0)

Output:

>>> popt
array([2.36403281e-01, 9.08178303e+02, 2.68108346e-03])

>>>pcov
array([[ 1.30221168e-03,  7.18606249e-04, -5.22339673e-06],
   [ 7.18606249e-04,  4.48554164e-04, -3.15605374e-06],
   [-5.22339673e-06, -3.15605374e-06,  2.25596318e-08]])

Here's how the fitted data and original data look like:

Here is the data I'm trying to fit (look at the attached image for how it looks) Time
907.6, 907.61, 907.62, 907.63, 907.64, 907.65, 907.66, 907.67, 907.68, 907.69, 907.7, 907.71, 907.72, 907.73, 907.74, 907.75, 907.76, 907.77, 907.78, 907.79, 907.8, 907.81, 907.82, 907.83, 907.84, 907.85, 907.86, 907.87, 907.88, 907.89, 907.9, 907.91, 907.92, 907.93, 907.94, 907.95, 907.96, 907.97, 907.98, 907.99, 908.0, 908.01, 908.02, 908.03, 908.04, 908.05, 908.06, 908.07, 908.08, 908.09, 908.1, 908.11, 908.12, 908.13, 908.14, 908.15, 908.16, 908.17, 908.18, 908.19, 908.2, 908.21, 908.22, 908.23, 908.24

Intensity

0.057805967, 0.5065527, -0.3501974, 0.036141705, 0.035738964, 0.23803276, 0.6114219, -0.3501108, 0.07225589, 0.18216568, 0.25470826, 0.20328628, 0.091083646, 0.5306828, 0.87142694, 1.1959167, 1.2584509, 1.5770732, 1.5870125, 1.844547, 1.5854758, 2.0418897, 3.0503955, 2.5744607, 2.6155453, 2.9460716, 3.3898244, 3.5842943, 3.2935236, 3.3901217, 4.2156982, 3.4158673, 4.341926, 4.3702006, 3.9515905, 4.3101573, 4.2822328, 4.8445034, 4.2415953, 4.7157598, 4.856417, 4.842477, 4.6342535, 4.820195, 5.348257, 4.5149198, 4.8444476, 4.681948, 4.8084526, 4.7724895, 4.3835893, 4.362606, 4.529179, 4.8953743, 4.4109926, 4.924057, 5.0648174, 4.793385, 4.6049685, 4.6032906, 5.037164, 5.379293, 4.9395213, 4.7802463, 4.234617