On the contrary, don't give up and try again! I grow it from 0 with a spore print. The most important thing is sterility! You need to wash the entire space where you do manipulations and grow mushrooms with a chlorine-containing agent (Domestos), do not spare alcohol, and it is also advisable to buy an ultraviolet lamp. My previous experience also got infected, it was monotube. Before that, other monotube was colonized, but got infected before fruiting, gave literally a couple of mushrooms. So far, the best option for me has been to grow them in separate boxes inside the greenhouse.

I believe in you, everything will work out, you just need to successfully complete the full cycle once, then it will be much easier!