Inner side tube punctures

[Krijes]

I haven't been riding a bike for about two years, before that I was riding it extensively for about 5 or more years. It is a 26 inch mountain bike (if that matters at all).
The bike was just staying on flat tires for these two years.
After i decided to put the bike to life again so to speak I started to get inner tube punctures (punctures on a tube from the inner side, the side not facing the road) almost on a daily basis. Only on a rear wheel. (I'm not too heavy -95kg)
So, I searched for some AI solutions and possible causes of this problem, and mainly it points out either to a worn out wheel tape or some sharp place on the rim which causes these punctures.
I inspected both the wheel itself by searching for a possible sharp spot and also I inspected the puncture places on 2 punctured tubes themselves. So what is confusing to me is that i haven't found any obvious sharp place when inspecting the rim by going with my fingers over the tape nor the places of punctures on the tubes themselves are on the same place, one is you could say right on the valve point itself and the other one is pretty near the valve, a few inches or an inch.
So I thought can i use the duct tape as a temporary solution to this, or the problem can be in something different entirely?

Any suggestions and thoughts additional questions, and possible solutions to this problem are welcomed.
Thank you -)

[rydabent]

Or---------maybe you just have a seam failure.

[ReapThaWhirlwind]

Maybe you're not riding the tires with enough PSI also.

If you did this a lot, you can wear out the sidewalls. It could also be a pinch flat from this same reason.

You might need to replace the tires.