u/2thirds

Anyone know what's going on?

During a house remodel my house was repainted in the December time frame. When doing some touch ups I noticed some bubbling paint on an exterior post. I assumed it was moisture given the time of year of the repainting.

I've tried various combinations of sanding, TSP and drydex patching, but it keeps coming back after three attempts. Bad paint? Something else?

Edit: photos

https://preview.redd.it/u6n43nepre1h1.jpg?width=3024&format=pjpg&auto=webp&s=3f08e4538e18a8e1341d299aab3752226e0823de

https://preview.redd.it/xzo3mnepre1h1.jpg?width=3024&format=pjpg&auto=webp&s=8e7b9ef80e4b0f528a3d2e5c83eba68d3825d040