Volvo warning light: Automatic Transmission Service Required on 2001 Volvo S80

My car's 4 speed (P-R-N-D-3-2-1)automatic transmission is not working properly it's slipping for R speed and making noisy jerks for any forward speed while shifting. Mileage is about 110,000. I am too much worried what to do next. A nearby mechanic says that it's some electronical fault and can be reset by vida-dice, while anotherone says that it should be opened and fully serviced. Can anybody help me with the right guidence, what I should do now. Is there any alternative transmission from any other car which can be fitted in my volvo model. Thanking in advance. (should I buy Volvo Vida-Dice from online e-bay? Would it be helpfull for me?)

Asked by for the 2001 Volvo S80
Unfortunately Volvo has chosen a GM transmission instead of the Aisin as they did before.
When dealers sold these cars they told the costumers that transmission is filled with lifetime fluid so fluid does not need to be replaced. As soon as the warranty run out these transnissions got bad one after the other.
I have replaced many of them myself.
Try the new software first it may help but by the symptoms you described the transmission had mechanical fault.
Hi there, Thank you for your advice. I will try first to reset the software as well as to replace oil and filter. Can you guess by the symptoms what can be the mechanical fault? Few days ago a mechanic replaced a new heating house pype and than re-filled with antifreez instead of permant, actually he mixed antifreez with earlier permant, so is it causing any electronical or mechanical fault inside? Thanks.