i have a similar problem
when i use a shelly 2.5 on 24v, getting /status from ip shows useless values 0.08 and sometimes 0.07, but never anything nearby 24v
when i use the same shelly on a 220v connection, a proper value is always shown
does the shelly 2.5 voltage measuring does not work with 24v dc? or is there any wrong setting
would be nice if i could use voltage also for battery monitoring