Or start a new cartridge to be on safe side?
I cannot find anything on the internet about a change in Lantus; there are other varieties of insulin glargine around:-
1: Lantus - the original glargine insulin (100 units per ml)
2: Toujeo - stronger strength glargine, 300 units per ml
3: Abasaglar - standard biosimilar insulin (U100) which looks like lantus and should behave like Lantus but is not garuanteed to behave exactly like Lantus (it is also a bit cheaper)
Are you on the same "lantus" as before?
Best wishes