advice for training barks and reacting

Hi! I have an antsy preteen I think lmao she’s a 7.5 months old maltipoo (real small dog energy).

She’s been barking so much more in the last two months for various reasons. It’s like she goes from 0-100 there is so gradual buildup or anything, she just goes batshit crazy.

Most of the time it’s barrier frustration. She wants to be close to something she is physically unable too.

Shes been recovering from her spay and it hasn’t been bad with trazedone but we are pet sitting and when she sees him but can’t play she goes crazyyyy and it feels random sometimes.

I know barking is naturally, and I’m working on “recovery” so her bouncing back from whatever it is thats triggering her but does anybody have advice? What’s helped you keep the barking under control?