If it's broken, you find out what is wrong/what changed and adapt. Access is a bit lacking in security compared to other apps but generally speaking, if there is something "wrong" when it worked for some time then it could be the introduction of a bug due to less than perfect releases of new versions. Sometimes new releases expose less than perfect code, which introduces failures to perform as expected, and that is on the code writer, not Access.
If you want a less general/ambiguous answer, you'd have to provide more information than "something is wrong". You always have the option to post a compacted and zipped db copy if you think it might help others to help you.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.