Cannot access offset of type string on string

error: 0
file: /var/www/html/xtremboy-www/class/Tools/Telegram.php
line: 14

{
    "file": "/var/www/html/xtremboy-www/__webui.php",
    "line": 64,
    "function": "telegram_config",
    "class": "Tools_Telegram",
    "type": "::"
}

{
    "file": "/var/www/html/xtremboy-www/index.php",
    "line": 68,
    "function": "ui_render"
}