let val = process.env[key];

[LightSN]

home/pi/Desktop/node_modules/pi-arest/node_modules/mqtt/node_modules/debug/src/node.js:132
let val = process.env[key];
^^^

SyntaxError: Block-scoped declarations (let, const, function, class) not yet supported outside strict mode
at exports.runInThisContext (vm.js:53:16)
at Module._compile (module.js:373:25)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Object. (/home/pi/Desktop/node_modules/pi-arest/node_modules/mqtt/node_modules/debug/src/index.js:9:19)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)

Error occurs on raspberry pi 4b, i did everything from tutorial how to add rpi to arest cloud. Any ideas what is wrong?