Hello Alison,
Please try by;
1. Flushing the browser cache or any caching plugin you might be running.
2. Deactivating all the plugins temporarily and checking if that solves the issue. If it works, try to reactivate theme one by one for detecting the actual plugin that is creating the conflict.
3. Also try switching temporarily to any standard wordpress theme like twenty seventeen and finding if the issue still persists or not.
Let us know.
Thanks!