Have tried several ways, how can I stop grass growing in flower beds?

Smother the grass out with newspapers,cardbaord ,professional landscape fabric and top with mulch

Smother with newspaper, cardboard or landscape fabric, then place mulch on top.

Hoe, get as much grass out as you can then smother it...cardboard, newspaper, black garbage bags...wood chips.

Deep mulch. I usually place sheets of corrugated cardboard on dirt, then cover w mulch. About 4+”

It always helps if you can tell us what you have done so we have some place to start. Otherwise we will likely give advice that you have already tried and are dissatisfied with results. Off-hand, the first thing I would ask is if you have installed a rhizome barrier. That is the best place to start.

Grass and other weeds WILL find a way to grow where there is nothing else growing. It is what they do. Your only option is to keep working at discouraging it from growing where you don't want it.

try using a systemic grass killer-they target only grasses,and will leave perennials alone-there are also weed killers in a gel base that only kill the plant that they're placed on-while I try to be an organic gardener,in some of my flower gardens,I will occasionally encounter issues that require something stronger than a spray bottle of apple cider vinegar and water