ser.inwaiting returns 0 (b'') but should not

Question

I'm a rookie when it comes to programming but I'm learning. I'm trying to program my mini-pc (Rock 4 SE, with a connected 4G phat and GPS modem) to send GPS location with a python script through minicom. When running the script I can tell in minicom (GPS program) that the python script runs minciom (when sending AT+CGPSINFO it answers +CGPSINFO: 1234.56789 etc) and sends commands and gives the GPS location, but the script can't extract the information from the program.

#!/usr/bin/python
# -*- coding:utf-8 -*-
import serial
import time

ser = serial.Serial('/dev/ttyUSB2',115200)
ser.flushInput()

power_key = 6
rec_buff = ''
rec_buff2 = ''
time_count = 0

def send_at(command,back,timeout):
    rec_buff = ''
    ser.write((command+'\r\n').encode())
    time.sleep(timeout)
    if ser.inWaiting():
        time.sleep(0.01 )
        rec_buff = ser.read(ser.inWaiting())
    if rec_buff != '':
        if back not in rec_buff.decode():
            print(command + ' ERROR')
            print(command + ' back:\t' + rec_buff.decode())
            return 0
        else:
            
            #print(rec_buff.decode())
            
            #Additions to Demo Code Written by Tim!
            global GPSDATA
            #print(GPSDATA)
            GPSDATA = str(rec_buff.decode())
            Cleaned = GPSDATA[13:]
            
            #print(Cleaned)
            
            Lat = Cleaned[:2]
            SmallLat = Cleaned[2:11]
            NorthOrSouth = Cleaned[12]
            
            #print(Lat, SmallLat, NorthOrSouth)
            
            Long = Cleaned[14:17]
            SmallLong = Cleaned[17:26]
            EastOrWest = Cleaned[27]
            
            #print(Long, SmallLong, EastOrWest)   
            FinalLat = float(Lat) + (float(SmallLat)/60)
            FinalLong = float(Long) + (float(SmallLong)/60)
            
            if NorthOrSouth == 'S': FinalLat = -FinalLat
            if EastOrWest == 'W': FinalLong = -FinalLong
            
            print(FinalLat, FinalLong)
            
            #print(FinalLat, FinalLong)
            #print(rec_buff.decode())
            
            return 1
    else:
        print('GPS is not ready')
        return 0

def get_gps_position():
    rec_null = True
    answer = 0
    print('Start GPS session...')
    rec_buff = ''
    send_at('AT+CGPS=1,1','OK',1)
    time.sleep(2)
    while rec_null:
        answer = send_at('AT+CGPSINFO','+CGPSINFO: ',1)
        if 1 == answer:
            answer = 0
            if ',,,,,,' in rec_buff:
                print('GPS is not ready')
                rec_null = False
                time.sleep(1)
        else:
            print('error %d'%answer)
            rec_buff = ''
            send_at('AT+CGPS=0','OK',1)
            return False
        time.sleep(1.5)

#Additions to Demo GPS.py Code Added by Tim // Simplfing the GPS Start up process
power_on(power_key)
while True:
    
    get_gps_position()

I did some debugging and noticed that the command ser.inWaiting returns 0 when it should actually return the GPS location. Thanks for any help. NOTE: this code was originally made for a raspberry pi, but I have modified it and hope it will work for the Rock 4 SE. Sorry if I formulated this wrong or anything, this is the first time I post on stack overflow.

ser.inwaiting returns 0 (b'') but should not

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