Been Emergency taxed ( i think)

In February I worked a temp job under a agency , the same job also finished in February as it was only a couple of weeks , on the 15/04/26 I started a new permanent job at screwfix . I got paid today , the pay was only just under £600 and yet I got taxed just over £100 which is obviously wrong . I have already contacted my work but how do I go about sorting this ? . Has this happened because they thought i had two jobs ? . I have now declared i no longer work at the recruitment agency on the HMRC app but how long will this take to sort and who do I contact ? Im really stressed about this money and who do I contact to make sure im under the right tax code?.