Zoom to a plot with GeoPandas based on data from CSV and shapefile

Here is my code:

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
import descartes
import geopandas as gpd
from sklearn.cluster import KMeans
from sklearn.preprocessing import MinMaxScaler
from sklearn.decomposition import PCA
from shapely.geometry import Point, Polygon
from geopandas import GeoDataFrame as gdf
%matplotlib inline

street_map = gpd.read_file('C:UsersuserDownloadsraccoon_islandraccoon_island.shp')

fig,ax = plt.subplots(figsize = (15, 15)) 
street_map.plot(ax=ax)

df = pd.read_csv('F:AnacondadocsOneDrive_1_9-29-202011.csv')
df = df[['longitude_start','latitude_start']]
crs = {'init': 'epsg:4326'}
df.head() 

geometry = [Point(xy) for xy in zip( df["longitude_start"], df["latitude_start"])]
geometry[:3]

geo_df = gpd.GeoDataFrame(df, crs = crs, geometry = geometry)
geo_df.head()

fig,ax = plt.subplots(figsize = (15, 15))
street_map.plot(ax = ax, alpha = 0.4, color='grey')
geo_df.plot(ax=ax, color='red', markersize=20, marker = '+', label= 'pos')
plt.legend(prop={'size': 15})

I have tried the following but it only seems to make the outer box change size. I would like to zoom in on the result instead.

fig,ax = plt.subplots(figsize = (30, 30))
street_map.plot(ax = ax, alpha = 0.4, color='grey')
geo_df.plot(ax=ax, color='red', markersize=20, marker = '+', label= 'pos')
ax.set_ylim(auto=True)
plt.legend(prop={'size': 15})

ax.set(xlim=(xmin, xmax), ylim=(ymin, ymax))

minx, miny, maxx, maxy = gdf.total_bounds
ax.set_xlim(minx, maxx)
ax.set_ylim(miny, maxy)

fig,ax = plt.subplots(figsize = (30, 30))
street_map.plot(ax = ax, alpha = 0.4, color='grey')
geo_df.plot(ax=ax, color='red', markersize=20, marker = '+', label= 'pos')
plt.legend(prop={'size': 15})

minx, miny, maxx, maxy = gdf.total_bounds
ax.set_xlim(minx, maxx)
ax.set_ylim(miny, maxy)

import geopandas as gpd

world = gpd.read_file(gpd.datasets.get_path('naturalearth_lowres'))
africa = world[world.continent == 'Africa']
cities = gpd.read_file(gpd.datasets.get_path('naturalearth_cities'))

ax = africa.plot()
cities.plot(ax=ax, color='r')

minx, miny, maxx, maxy = africa.total_bounds
ax.set_xlim(minx, maxx)
ax.set_ylim(miny, maxy)