The GV250 has a good charging system, so the 1 st thing is to get the battery checked.
Use a battery tender and charge the battery fully.
Measure the voltage at the battery with the key off. It should read 12.5 volts
With the meter attached to the battery, turn on the ignition switch and monitor the voltage. It should drop to about 11.5 v.
and not drop much more.
Still monitoring the voltage, try to start the engine. If the voltage drops to below 10 v , the battery is bad.
And if the earlier values are low, the battery is probably bad.
You can have a garage or auto parts store make a "load test" on the battery instead, but you need the battery to be fully charged.
The usual rule of thumb, is that if you have a problem and the battery is more than 3 years old, get a new battery.
It is the easiest fix, but it may not be the problem, so you have to test it.
scoot safely,