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That's a rather strange thermal relief pattern.  It's also not clear where the hole is supposed to be.

A proper thermal pattern has a plated hole and annular ring around the hole as usual.  Then there is a gap with only a few narrow bridges connecting the annular ring with the surrounding plane.  It is common for there to be four bridges, each 90° from the next.  The total copper of the bridges is what defines the current capability of the pad and ultimately the connection.

Your picture doesn't show where the hole is.  Here is the only interpretation that makes any sense:

<img src="https://electrical.codidact.com/uploads/kTQkYJywato8Mc7uxvqhdK15">

Now we can see that you have a normal thermal pattern, except that the top bridge is much wider than the others.  If this top bridge were the same width as the other three, then you probably wouldn't have had any problems with soldering.

So why is the top bridge so wide?  You don't say what tool you are using, but you probably have some attribute set for this net that requires a certain minimum trace width.  The tool then had to resolve the conflicting requirements of needing to make a pad with thermal relief and needing a minimum trace thickness.  What this tool did in this case was apparently to start with a normal thermal pattern, then draw the wide trace over it.  The tool designers apparently didn't put a lot of effort into resolving these conflicting requirements from the user.

A better tool might have made each of the bridges &frac14; of the required trace width, then grown the whole thermal pattern as necessary to make it still work like a thermal pattern.  However, that could cause other problems.  Tools "automatically" fixing things can cause lots of trouble.

In the end, <i>you</i> need to resolve this by not providing conflicting requirements.  First, decide how much current this pad needs to carry, then use that to decide on the minimum required trace width.  Once you have that, set up the thermal pattern so that the four bridges add up to the minimum trace width, and grow its diameter as necessary so that the bridges add up to only a small fraction of the thermally-insulated ring.

If you really need high current capability, then maybe you don't get to use thermals at all, or they'd be so large to make them ineffective.  If that is the case, then you need to adjust your manufacturing practices accordingly.