Patta subdivided without our knowledge

Dear All requesting your heartfull suggestion,guidance and advice please. We are have property for 20+ years in one survey number with 6 subdivision in one patta for 12,14,15,16,17 that has only my fathers name for all these years and Subdivision 13 is a joint patta with our neighbours (both my neighbours and my fathers names are there) . To our surprise when we down loaded the patta few days back we found that 14 and 15 subdivision has been mentioned in our patta as 14a and 15a and when drilled down further found that a new patta has been issued as 13b,14b and 15b in the name of our neighbour  whoi s a joint in subdivision 13. Advice and and guidance  required 1. Can a subdivision happen with any info to us 2.How to i find out why this has happened  and how as well .. as we have not sold this property or did any transactions in this property. 3.How do i cancel this patta isssued 4. There is some remarks given in the last column of the patta with lots of numbers and in the end with date moth and year. What is it.