[Help] Txadmin error

Hello to all,

I come to solicit you concerning a problem of TxAdmin, indeed as soon as I connect on the web interface to add people in whitelist or management of the server, the server crashes.

I specify that the server is on personal Linux on the Pop!_OS distribution (computer reserved for the server).
I think I have opened the necessary ports as everyone can access the server.

Here is a screen of the error that the server gives me when I connect to the web interface.

Thanks to all for your help.