I work in sales. It's still a relatively new job and I'm about to have my probation review (which I will hopefully pass). So far I've had really good feedback from my line manager and am quite good at what I do. The problem is the colleagues on my team.
The role is office based and we sell our products via phone and email. When we get an enquiry we log details of it on the customer record and that then becomes our customer for 12 weeks from the date of enquiry. You can prolong the length which you have the customer by updating the enquiry. We all have our own targets (there are 3 of us who do the same role) and we earn commission ok anything over our targets. The targets were raised in April and a number of factors are making it difficult to reach target.
About two weeks ago one of my colleagues A basically doctored a record to make it look like a lead was theirs. A had added an enquiry and selected a date of a few weeks previous to mine to make it look like the customer had already been speaking to A when I know full well they hadn't. It was a lead worth quite a lot and A deferred it to our line manager to make the decision on who got to keep the lead. As I already had a different enquiry recorded before the doctored enquiry was added (which was a couple of weeks after my original enquiry was listed) the lead stayed with me. I did not mention to our line manager that my colleague had basically tried to steal the lead off me as I didn't want to cause any problems and I just let it go.
Today my other colleague B emailed me to say that one of my current leads belonged to her due to an existing enquiry on a linked record. At the time I was busy trying to sort something else and she came over to me to check I'd got the email. This lead only came in just over a week ago and I remember checking the customer record (as I normally do) for any existing enquiries. There was one from October last year and one from 1st February this year, both from B. We were past the 12 week ownership period so I recorded the enquiry and put my name to it. When I checked today one of the dates had been changed to 1st March which would have put the ownership back to B. B coming over put me on the spot so I said sorry if thought she was out of ownership but passed the details of my enquiry over to her as I didn't want to call her a liar then and there.
When I got a minute I checked the linked record and that customer would have actually belonged to me when she supposedly took another enquiry from them, as I had recorded an enquiry 5 weeks previously. Going back to the original record I realised that not only had she changed the date on the enquiry but she had basically changed the wording to the enquiry from October. I didn't call her on it and ask for the lead back, but have been stewing all day about this. That lead is mine, she's also doctored the record to try and make it look like it was her customer but has completely failed. This isn't the first time she's done this either and the first time she made a song and dance about it to colleague A, protecting her tracking sheet so no one could read it and talking about people taking her leads. This was aimed at me, because our line manager sometimes distributes leads and he hadn't checked whether a lead that came in already belonged to someone. The lead was passed to B but I already had an enquiry on it. Instead of passing the lead back to me she then went on a linked record and made out that the person who made the enquiry worked there. When the person got in touch to say they had heard nothing, our line manager checked and realised he should have passed it to me in the first place and then gave it back to me to chase up. I ended up getting the sale and she's been making out I've stolen it, when in fact she was trying to do that to me.
Anyway the dilemma I have is that I'm still relatively new and I've got a lot of other things going on right now so id prefer not to start having problems with colleagues. However, both A and B have effectively stolen leads from me. I'm really pissed off about today but if I ask for the lead back I will have to call B out on doctoring the record to make it look like its her customer. The way she also came over to me nice as pie and started going on about how she'd have let it go if she was close to her target and how we're all scrimping for leads 
The system isn't perfect and you can add enquiries to the record whenever you want with whatever date you want. I know they've both changed the records and the likelihood is that both of them will try and pull this stunt again in the future. AIBU to bring it up with my line manager and also ask B for my lead back? I don't really want to have to call either of them out on this and I can just foresee being given the cold shoulder/bitching behind my back if I escalate this. I just don't feel comfortable having to have that confrontation and am also wondering whether I now need to start screen shorting records when I put the enquiry on so I can back it up with evidence in future. WWYD?