Tech Casting – Limiting OP use with Modern Magic Ruleset

We’re many sessions into a homebrew cyberpunk 5E, and I’ve recently introduced hacking using this Modern Magic UA.

I can’t see in there any stipulation on how frequently a hacker class can cast a tech. Are there any hard and fast rules?

Context; my tech caster can load these hacks into a small portable ‘techdeck’ he carries around, and casts them from there. In last night’s session, he was able to basically run through an infiltration mission wildly casting Invisiblity to Cameras and Haywire on most challenges (it played out balanced enough in the end luckily, and didn’t ruin the story), but I’m just concerned it was a little OP.

So the question is… with Tech casting, is there a standardised limit I can impose on my players when they’re casting too many techs?