I am using esp32 and sim800c module.
I tried running the example but i am not be able to connect to the network.

Below is the full stack showing on serial monitor.

�[0;32mI (31) boot: ESP-IDF v4.2-dev-701-g0ae960f2f-dirty 2nd stage bootloader�[0m
�[0;32mI (31) boot: compile time 14:45:08�[0m
�[0;32mI (32) boot: chip revision: 1�[0m
�[0;32mI (36) boot_comm: chip revision: 1, min. bootloader chip revision: 0�[0m
�[0;32mI (43) boot.esp32: SPI Speed : 40MHz�[0m
�[0;32mI (47) boot.esp32: SPI Mode : DIO�[0m
�[0;32mI (52) boot.esp32: SPI Flash Size : 4MB�[0m
�[0;32mI (56) boot: Enabling RNG early entropy source...�[0m
�[0;32mI (62) boot: Partition Table:�[0m
�[0;32mI (65) boot: ## Label Usage Type ST Offset Length�[0m
�[0;32mI (73) boot: 0 nvs WiFi data 01 02 00009000 00006000�[0m
�[0;32mI (80) boot: 1 phy_init RF data 01 01 0000f000 00001000�[0m
�[0;32mI (88) boot: 2 factory factory app 00 00 00010000 00100000�[0m
�[0;32mI (95) boot: End of partition table�[0m
�[0;32mI (99) boot_comm: chip revision: 1, min. application chip revision: 0�[0m
�[0;32mI (106) esp_image: segment 0: paddr=0x00010020 vaddr=0x3f400020 size=0x17cf8 ( 97528) map�[0m
�[0;32mI (152) esp_image: segment 1: paddr=0x00027d20 vaddr=0x3ffb0000 size=0x022e8 ( 8936) load�[0m
�[0;32mI (156) esp_image: segment 2: paddr=0x0002a010 vaddr=0x40080000 size=0x00400 ( 1024) load�[0m
�[0;32mI (159) esp_image: segment 3: paddr=0x0002a418 vaddr=0x40080400 size=0x05c00 ( 23552) load�[0m
�[0;32mI (178) esp_image: segment 4: paddr=0x00030020 vaddr=0x400d0020 size=0x5a15c (368988) map�[0m
�[0;32mI (318) esp_image: segment 5: paddr=0x0008a184 vaddr=0x40086000 size=0x049a8 ( 18856) load�[0m
�[0;32mI (332) boot: Loaded app from partition at offset 0x10000�[0m
�[0;32mI (332) boot: Disabling RNG early entropy source...�[0m
�[0;32mI (333) cpu_start: Pro cpu up.�[0m
�[0;32mI (336) cpu_start: Application information:�[0m
�[0;32mI (341) cpu_start: Project name: pppos_client�[0m
�[0;32mI (346) cpu_start: App version: 1�[0m
�[0;32mI (351) cpu_start: Compile time: May 8 2020 14:45:14�[0m
�[0;32mI (357) cpu_start: ELF file SHA256: 04d24dea9b28bffb...�[0m
�[0;32mI (363) cpu_start: ESP-IDF: v4.2-dev-701-g0ae960f2f-dirty�[0m
�[0;32mI (370) cpu_start: Starting app cpu, entry point is 0x40081168�[0m
�[0;32mI (0) cpu_start: App cpu up.�[0m
�[0;32mI (380) heap_init: Initializing. RAM available for dynamic allocation:�[0m
�[0;32mI (387) heap_init: At 3FFAE6E0 len 00001920 (6 KiB): DRAM�[0m
�[0;32mI (393) heap_init: At 3FFB3E18 len 0002C1E8 (176 KiB): DRAM�[0m
�[0;32mI (399) heap_init: At 3FFE0440 len 00003AE0 (14 KiB): D/IRAM�[0m
�[0;32mI (406) heap_init: At 3FFE4350 len 0001BCB0 (111 KiB): D/IRAM�[0m
�[0;32mI (412) heap_init: At 4008A9A8 len 00015658 (85 KiB): IRAM�[0m
�[0;32mI (418) cpu_start: Pro cpu start user code�[0m
�[0;32mI (437) spi_flash: detected chip: generic�[0m
�[0;32mI (437) spi_flash: flash io: dio�[0m
�[0;32mI (437)⸮AT
+++ATH
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ATH
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ATH

please help me resolving this issue.