GSM MUX reinitialization

[bis50]

Good day.

I'm using SIM7500E GSM modem in mux mode (CONFIG_GSM_MUX). After issuing mux mode enabling at-command modem is ready to accept commands and this function works fine. To do this I call uart_mux_attach() for 3 DLCI identifiers:

r = uart_mux_attach(mdata->control_dev, mdata->uart_dev, DLCI_CONTROL, mux_attach_cb, (void*)mdata);
r = uart_mux_attach(mdata->ppp_dev, mdata->uart_dev, DLCI_PPP, mux_attach_cb, (void*)mdata);
r = uart_mux_attach(mdata->at_dev, mdata->uart_dev, DLCI_AT, mux_attach_cb, (void*)mdata);

Then I initialize mux channel DLCI_AT:

modem_iface_uart_init_dev( &mdata->context.iface, mdata->at_dev );

And send at commands.

The question is: what functions should I call to close mux connection if modem is restarted. I tried to call uart_mux_disable() and gsm_mux_disconnect(). But when I call uart_mux_attach() for the second time after restarting modem the controller hangs without any fault output.