MTS 950 Fuel Sender Issue

Hi guys,
Took the bike out today for it’s first ride in quite a while. First job was to get fuel and I noticed the fuel guage didn’t move from 3 bars. Rode about 40 miles, brief stop, fuel guage now reading nearly full. Seemed to come down quite quickly and after about 130 miles warning light came on with gauge on 2 bars. Filled up, warning light went out but guage didn’t move up. I’m currently using the trip to watch fuel requirements.

So what’s the verdict? Is this a symptom of not using the bike and it will right itself with use or is it a new sender job?

Thanks in advance…