crashes on 1.18.2 when using the currency converter

[crash-2023-09-05_17.46.13-server.txt](https://github.com/screret/VendingMachine/files/12529845/crash-2023-09-05_17.46.13-server.txt)
[debug.log](https://github.com/screret/VendingMachine/files/12529849/debug.log)
[Log_2023-08-24_130044.txt](https://github.com/screret/VendingMachine/files/12529850/Log_2023-08-24_130044.txt)
