How can I help my best friends be the way they were?

ok I moved school on the 27th of august. I finished primary school and I moved into secondary. there are 3 girls going to my school - Leixlip Secondary. I knew 1 of them quite well, and the others were in my class too, but they weren’t my ‘best friends’! anyways, there’s wendy, the girl I no well - hannah, 1 of the other girls and Sarah the other one! lol so, Hannah and Sarah have been bffs 4ever - and I mean 4ever. but when we moved school, we were divided up into forms and we were all split up. we all found new friends and all, but I was tlkin 2 Hannah 1 lunchtime and Sarah was walkin by. normally we wave at eachother and stuff, but Sarah has these new friends and none of us have been introduced to them (unlike my friends, etc.) so hannah said to me ‘I havent been tlkin 2 sarah in ages’ and its true. I nodded. sarah and hannah used to b inseperable - now, it’s changed… im worried 4 them… I no this probably happens ALL the time in new schools and all, but, Sarah is just making the whole ‘moving schools’ thing harder 4 Hannah rite now… HELP!