DataLoader takes as parameters batch_size = foo. As such it returns batches of batch_size. The exception to this being the final batch. this happens if the length of your data_set is not divisible by the batch_size.
perhaps you may want to structure your data differently
consider this shape for your batches:
[batch_size, seq_length, input_size]
batch_size = number of people per batch this is fixed
seq_length = number of instances from that user
input_size = length of those instances
Depending on what model you are using you may need to pad your seq_length and input_size so that they are all of the same length.
example:
you have dataset of people names
bob
alice
edward
where each row corresponds to one person.
In this case:
input_size: is the length of your one hot encode for the name and
seq_length: is the length of the name
batch_size: is the number of people you will process at one time. This is fixed.
You did not provide very many details so this is the most I can do to help.
edit: example with names I gave did not account for encoding which would be necessary.