Battery discharge

The leisure battery on my Autosleeper Symbol 2011 motorhome 
does not appear to be charging and I need to check it out for possible
replacement but I'm not sure of its location.....Any advice please .?

Under drivers seat?

Thanks Paul.....No nothing under the drivers seat but have now located it under the side bench ....thanks for your prompt.

yes  in our 2019 symbol   LB is under the off side seat/ single bed ..ours is on charge. on  the home EHU off soon for our wedding anniversary , we met on a field .got married 3 years back .
remember if using a metal spanner on the battery do Not short it out on the bed frame or your self .

Thanks Dave......yes I'll be careful.....I use an EHU during winter months but this time the condition meter in the van is showing the battery fully charge when im charging but when I turn off the mains it consustently  drops to red.
Congratualations on your anniversary trip away .
John

Take off charge and test the voltage with a multimeter, it should be around 12.7 volts after an hour of the charger , if it’s dropping sounds as thought the battery need’s replacing