Cat vomits about twice a week

Hi everyone,

My 1 year old girl has been vomiting her wet food about twice a week.

Tried different food (high quality) but it doesn’t matter what flavor or protein. Currently she’s on Weruva classic pate.
She doesn’t seem to eat too fast.

The vet doesn’t have a clue

Not sure what to do about this. Could this be simply IBD?

If it’s a food sensitivity I wonder why it’s just twice a week. Makes no sense.

Does anyone have a cat who had the same issue?